From patchwork Mon Nov 18 10:13:03 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 844599 Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0675B1925B3; Mon, 18 Nov 2024 10:13:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731924800; cv=none; b=H4/047nNWdnjZMtlLrO8fllEVRDEcy/H6RAqskX5EtBx52gJYXgl07OhidCK5ZRnLJmsFweE6qQclsRHI0MPd3H7Y3MZH+yKBTPbRniVv5QBLq13ykIh+B22nuKDy5u1cmDwWIQ9P2qGsFjm2agWlcrntubPLSnTBZrjJezZe98= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731924800; c=relaxed/simple; bh=ybftUMxFeXNrw4AE2s143r0M00oklLUIBb8THoHDFXs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=mGEcnjO5xlhekwSKokxJdTBqClsUxlSZCfHvvQD+wDigXOqNHdfLYC387PkAYNfodOlSR6Xrh+BK2uZRN/XYwA6llfrLDop4sjeeIhT+V6sA31saPTIQq2WQC0tbXdbrggD/IwsRfRkSxuIJUBy7lYbEl+WMgVmbNYLYwMKpN78= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=IGbC2Ke6; arc=none smtp.client-ip=217.70.183.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="IGbC2Ke6" Received: by mail.gandi.net (Postfix) with ESMTPSA id B9E371BF205; Mon, 18 Nov 2024 10:13:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731924795; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=eDMqNXN+UYqyQqUu1V62RNFnYP8XOvywWsZyr2uIKsA=; b=IGbC2Ke61fDormaVlj8tLjXHqnzYKW/vImL71YAy4auK4nBizEgG/cnoVR8KtJeJOWoBRD j0SIsqWt/MF4C6KcDo6tDgeX7CVLJHPSKfn1idje0YwkOikESlPenAq9bbbfBR1CmjzcFm u8izYjzudo8NOU4R8uUpZDvTrK5D29jjUpU/7WZkkEKILHBBiEH2BKCkun9STBMQqhnGdF jj/3CIe4T3yKPbhewXmANGPR7JGjNDnm5Mt848pVzDfydnYBEnwcek8628VHx1WMxfh9ju 6TU5B+qSuahyHT67Fw9daFQ8z67LwhV2ISURx2uI7NeZwtrL82MTNjlSbq5rww== From: Romain Gantois Date: Mon, 18 Nov 2024 11:13:03 +0100 Subject: [PATCH v2 4/9] i2c: use client addresses directly in ATR interface Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241118-fpc202-v2-4-744e4f192a2d@bootlin.com> References: <20241118-fpc202-v2-0-744e4f192a2d@bootlin.com> In-Reply-To: <20241118-fpc202-v2-0-744e4f192a2d@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab , Linus Walleij , Bartosz Golaszewski Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, linux-gpio@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com The I2C Address Translator (ATR) module defines mappings from i2c_client structs to aliases. However, only the physical address of each i2c_client struct is actually relevant to the workings of the ATR module. Moreover, some drivers require address translation functionality but do not allocate i2c_client structs, accessing the adapter directly instead. The SFP subsystem is an example of this. Replace the "i2c_client" field of the i2c_atr_alias_pair struct with a u16 "addr" field. Rewrite helper functions and callbacks as needed. Signed-off-by: Romain Gantois --- drivers/i2c/i2c-atr.c | 52 ++++++++++++++++--------------------------- drivers/media/i2c/ds90ub960.c | 20 ++++++++--------- include/linux/i2c-atr.h | 20 ++++++++--------- 3 files changed, 39 insertions(+), 53 deletions(-) diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c index f21475ae592183a45b5e46a20e7a0699fb88132c..894787246846b9965deb03a7ec7eb600b102ddad 100644 --- a/drivers/i2c/i2c-atr.c +++ b/drivers/i2c/i2c-atr.c @@ -21,16 +21,16 @@ #define ATR_MAX_SYMLINK_LEN 11 /* Longest name is 10 chars: "channel-99" */ /** - * struct i2c_atr_alias_pair - Holds the alias assigned to a client. + * struct i2c_atr_alias_pair - Holds the alias assigned to a client address. * @node: List node - * @client: Pointer to the client on the child bus + * @addr: Address of the client on the child bus. * @alias: I2C alias address assigned by the driver. * This is the address that will be used to issue I2C transactions * on the parent (physical) bus. */ struct i2c_atr_alias_pair { struct list_head node; - const struct i2c_client *client; + u16 addr; u16 alias; }; @@ -97,27 +97,13 @@ struct i2c_atr { struct i2c_adapter *adapter[] __counted_by(max_adapters); }; -static struct i2c_atr_alias_pair * -i2c_atr_find_mapping_by_client(const struct list_head *list, - const struct i2c_client *client) -{ - struct i2c_atr_alias_pair *c2a; - - list_for_each_entry(c2a, list, node) { - if (c2a->client == client) - return c2a; - } - - return NULL; -} - static struct i2c_atr_alias_pair * i2c_atr_find_mapping_by_addr(const struct list_head *list, u16 phys_addr) { struct i2c_atr_alias_pair *c2a; list_for_each_entry(c2a, list, node) { - if (c2a->client->addr == phys_addr) + if (c2a->addr == phys_addr) return c2a; } @@ -313,8 +299,8 @@ static void i2c_atr_release_alias(struct i2c_atr *atr, u16 alias) dev_warn(atr->dev, "Unable to find mapped alias\n"); } -static int i2c_atr_attach_client(struct i2c_adapter *adapter, - const struct i2c_client *client) +static int i2c_atr_attach_addr(struct i2c_adapter *adapter, + u16 addr) { struct i2c_atr_chan *chan = adapter->algo_data; struct i2c_atr *atr = chan->atr; @@ -334,14 +320,14 @@ static int i2c_atr_attach_client(struct i2c_adapter *adapter, goto err_release_alias; } - ret = atr->ops->attach_client(atr, chan->chan_id, client, alias); + ret = atr->ops->attach_addr(atr, chan->chan_id, addr, alias); if (ret) goto err_free; - dev_dbg(atr->dev, "chan%u: client 0x%02x mapped at alias 0x%02x (%s)\n", - chan->chan_id, client->addr, alias, client->name); + dev_dbg(atr->dev, "chan%u: addr 0x%02x mapped at alias 0x%02x\n", + chan->chan_id, addr, alias); - c2a->client = client; + c2a->addr = addr; c2a->alias = alias; list_add(&c2a->node, &chan->alias_list); @@ -355,16 +341,16 @@ static int i2c_atr_attach_client(struct i2c_adapter *adapter, return ret; } -static void i2c_atr_detach_client(struct i2c_adapter *adapter, - const struct i2c_client *client) +static void i2c_atr_detach_addr(struct i2c_adapter *adapter, + u16 addr) { struct i2c_atr_chan *chan = adapter->algo_data; struct i2c_atr *atr = chan->atr; struct i2c_atr_alias_pair *c2a; - atr->ops->detach_client(atr, chan->chan_id, client); + atr->ops->detach_addr(atr, chan->chan_id, addr); - c2a = i2c_atr_find_mapping_by_client(&chan->alias_list, client); + c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, addr); if (!c2a) { /* This should never happen */ dev_warn(atr->dev, "Unable to find address mapping\n"); @@ -374,8 +360,8 @@ static void i2c_atr_detach_client(struct i2c_adapter *adapter, i2c_atr_release_alias(atr, c2a->alias); dev_dbg(atr->dev, - "chan%u: client 0x%02x unmapped from alias 0x%02x (%s)\n", - chan->chan_id, client->addr, c2a->alias, client->name); + "chan%u: addr 0x%02x unmapped from alias 0x%02x\n", + chan->chan_id, addr, c2a->alias); list_del(&c2a->node); kfree(c2a); @@ -405,7 +391,7 @@ static int i2c_atr_bus_notifier_call(struct notifier_block *nb, switch (event) { case BUS_NOTIFY_ADD_DEVICE: - ret = i2c_atr_attach_client(client->adapter, client); + ret = i2c_atr_attach_addr(client->adapter, client->addr); if (ret) dev_err(atr->dev, "Failed to attach remote client '%s': %d\n", @@ -413,7 +399,7 @@ static int i2c_atr_bus_notifier_call(struct notifier_block *nb, break; case BUS_NOTIFY_DEL_DEVICE: - i2c_atr_detach_client(client->adapter, client); + i2c_atr_detach_addr(client->adapter, client->addr); break; default: @@ -506,7 +492,7 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, if (max_adapters > ATR_MAX_ADAPTERS) return ERR_PTR(-EINVAL); - if (!ops || !ops->attach_client || !ops->detach_client) + if (!ops || !ops->attach_addr || !ops->detach_addr) return ERR_PTR(-EINVAL); atr = kzalloc(struct_size(atr, adapter, max_adapters), GFP_KERNEL); diff --git a/drivers/media/i2c/ds90ub960.c b/drivers/media/i2c/ds90ub960.c index 84aa976bed2d74f1d639684601f4c1c38d748188..5a836731af6c701ef4070eb2dbab36cbdd86e0a2 100644 --- a/drivers/media/i2c/ds90ub960.c +++ b/drivers/media/i2c/ds90ub960.c @@ -1026,8 +1026,8 @@ static int ub960_ind_update_bits(struct ub960_data *priv, u8 block, u8 reg, * I2C-ATR (address translator) */ -static int ub960_atr_attach_client(struct i2c_atr *atr, u32 chan_id, - const struct i2c_client *client, u16 alias) +static int ub960_atr_attach_addr(struct i2c_atr *atr, u32 chan_id, + u16 addr, u16 alias) { struct ub960_data *priv = i2c_atr_get_driver_data(atr); struct ub960_rxport *rxport = priv->rxports[chan_id]; @@ -1047,20 +1047,20 @@ static int ub960_atr_attach_client(struct i2c_atr *atr, u32 chan_id, set_bit(reg_idx, rxport->alias_use_mask); ub960_rxport_write(priv, chan_id, UB960_RR_SLAVE_ID(reg_idx), - client->addr << 1); + addr << 1); ub960_rxport_write(priv, chan_id, UB960_RR_SLAVE_ALIAS(reg_idx), alias << 1); dev_dbg(dev, "rx%u: client 0x%02x assigned alias 0x%02x at slot %u\n", - rxport->nport, client->addr, alias, reg_idx); + rxport->nport, addr, alias, reg_idx); out_unlock: mutex_unlock(&rxport->alias_mask_lock); return ret; } -static void ub960_atr_detach_client(struct i2c_atr *atr, u32 chan_id, - const struct i2c_client *client) +static void ub960_atr_detach_addr(struct i2c_atr *atr, u32 chan_id, + u16 addr) { struct ub960_data *priv = i2c_atr_get_driver_data(atr); struct ub960_rxport *rxport = priv->rxports[chan_id]; @@ -1073,7 +1073,7 @@ static void ub960_atr_detach_client(struct i2c_atr *atr, u32 chan_id, if (reg_idx >= UB960_MAX_PORT_ALIASES) { dev_err(dev, "rx%u: client 0x%02x is not mapped!\n", - rxport->nport, client->addr); + rxport->nport, addr); goto out_unlock; } @@ -1082,15 +1082,15 @@ static void ub960_atr_detach_client(struct i2c_atr *atr, u32 chan_id, ub960_rxport_write(priv, chan_id, UB960_RR_SLAVE_ALIAS(reg_idx), 0); dev_dbg(dev, "rx%u: client 0x%02x released at slot %u\n", rxport->nport, - client->addr, reg_idx); + addr, reg_idx); out_unlock: mutex_unlock(&rxport->alias_mask_lock); } static const struct i2c_atr_ops ub960_atr_ops = { - .attach_client = ub960_atr_attach_client, - .detach_client = ub960_atr_detach_client, + .attach_addr = ub960_atr_attach_addr, + .detach_addr = ub960_atr_detach_addr, }; static int ub960_init_atr(struct ub960_data *priv) diff --git a/include/linux/i2c-atr.h b/include/linux/i2c-atr.h index 4d5da161c22516b3294e73702ace7a4546cdd588..14c1f9175c0db6a8a9c6ef5d771ae68361132a76 100644 --- a/include/linux/i2c-atr.h +++ b/include/linux/i2c-atr.h @@ -20,20 +20,20 @@ struct i2c_atr; /** * struct i2c_atr_ops - Callbacks from ATR to the device driver. - * @attach_client: Notify the driver of a new device connected on a child - * bus, with the alias assigned to it. The driver must - * configure the hardware to use the alias. - * @detach_client: Notify the driver of a device getting disconnected. The - * driver must configure the hardware to stop using the - * alias. + * @attach_addr: Notify the driver of a new device connected on a child + * bus, with the alias assigned to it. The driver must + * configure the hardware to use the alias. + * @detach_addr: Notify the driver of a device getting disconnected. The + * driver must configure the hardware to stop using the + * alias. * * All these functions return 0 on success, a negative error code otherwise. */ struct i2c_atr_ops { - int (*attach_client)(struct i2c_atr *atr, u32 chan_id, - const struct i2c_client *client, u16 alias); - void (*detach_client)(struct i2c_atr *atr, u32 chan_id, - const struct i2c_client *client); + int (*attach_addr)(struct i2c_atr *atr, u32 chan_id, + u16 addr, u16 alias); + void (*detach_addr)(struct i2c_atr *atr, u32 chan_id, + u16 addr); }; /** From patchwork Mon Nov 18 10:13:04 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 844598 Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2F9AB192D95; Mon, 18 Nov 2024 10:13:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731924801; cv=none; b=bJvXYHR8R/fE8tNXysQTi35I2n9qmCC80s3jARGMNcQIIu7PsK1o44vqD4Bq3sg8RTWQmgDyZTMbh5eG++29xTnocr/uT044btfNTD6kEDNzl8247i/KXmk+1f1Qfj4z4LYo6r4Oln6adtCrXvKaRxZKZ8iFBhBCGuSj9hyabNY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731924801; c=relaxed/simple; bh=kxeO51kOwYXUp0OU5P8vMOAk78cA1NW78/VhRsNmjZU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=AyNoJ3+p/SFkXyyvan2yDagc3l+99r8cUMx1TVWajYtaHIv6ujBgwB+t0ZKRgu8PbOTVacgBSwGejznHjprCCVn7qfLbp2ZO56JOP39aSTGwHwn+Nu7h9fLraqyutsu3nLF3iPjCb5Leup8jw3BVdWxLZo2lWEiqxqCgul4Q5XI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=mJMcEWdm; arc=none smtp.client-ip=217.70.183.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="mJMcEWdm" Received: by mail.gandi.net (Postfix) with ESMTPSA id 5318E1BF210; Mon, 18 Nov 2024 10:13:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731924796; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=uO2oXC73Ucf+OKFHsX5fbRnrJrLCb2JkxdDG4pxP7Tk=; b=mJMcEWdm7INaLTpiTZ2E8JZ4A+FV3l2+htymH+K8p6sqYWwR/aiOM/DtQMxZ6lvJaFuDlX qJMHSiLQ74qK05wuFbMeAMA3z544XNAAwHxinOLJD01L1PgsrWEpc03rCbh9p63pI5iLkp RTrq4WsTxXQDBqB1hzx3FnBJ8aVwY43nmR2ttWkZCzr9/norQdPo3Ekb/D5pRlu8mib5wX EhmLPWlkQG6qrzwJEeAWwPypcFmhpu1YhXKFCWyOz1MVdyFCi3l2UoqfWo9ivBEkeB/pbR 68PsISjIOyOsnbxzQUH4LJnYrbOy5r4+XI0y+KAARMcdKIM0zmZKRCh40ZyPoQ== From: Romain Gantois Date: Mon, 18 Nov 2024 11:13:04 +0100 Subject: [PATCH v2 5/9] i2c: move ATR alias pool to a separate struct Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241118-fpc202-v2-5-744e4f192a2d@bootlin.com> References: <20241118-fpc202-v2-0-744e4f192a2d@bootlin.com> In-Reply-To: <20241118-fpc202-v2-0-744e4f192a2d@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab , Linus Walleij , Bartosz Golaszewski Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, linux-gpio@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com Each I2C address translator (ATR) has a pool of client aliases which can be used as translation targets. Some ATRs have a single alias pool shared by all downstream channels, while others have a separate alias pool for each channel. Currently, this alias pool is represented by the "aliases", "num_aliases", and "use_mask" fields of struct i2c_atr. In preparation for adding per-channel alias pool support, move the "aliases", "num_aliases", "use_mask" and associated lock to a new struct called "struct alias_pool". Signed-off-by: Romain Gantois --- drivers/i2c/i2c-atr.c | 172 +++++++++++++++++++++++++++++++------------------- 1 file changed, 107 insertions(+), 65 deletions(-) diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c index 894787246846b9965deb03a7ec7eb600b102ddad..c873fe52288175151040a4c32e6ed07735586004 100644 --- a/drivers/i2c/i2c-atr.c +++ b/drivers/i2c/i2c-atr.c @@ -34,6 +34,23 @@ struct i2c_atr_alias_pair { u16 alias; }; +/** + * struct i2c_atr_alias_pool - Pool of client aliases available for an ATR. + * @size: Total number of aliases + * + * @lock: Lock protecting @aliases and @use_mask + * @aliases: Array of aliases, must hold exactly @size elements + * @use_mask: Mask of used aliases + */ +struct i2c_atr_alias_pool { + size_t size; + + /* Protects aliases and use_mask */ + spinlock_t lock; + u16 *aliases; + unsigned long *use_mask; +}; + /** * struct i2c_atr_chan - Data for a channel. * @adap: The &struct i2c_adapter for the channel @@ -67,10 +84,7 @@ struct i2c_atr_chan { * @algo: The &struct i2c_algorithm for adapters * @lock: Lock for the I2C bus segment (see &struct i2c_lock_operations) * @max_adapters: Maximum number of adapters this I2C ATR can have - * @num_aliases: Number of aliases in the aliases array - * @aliases: The aliases array - * @alias_mask_lock: Lock protecting alias_use_mask - * @alias_use_mask: Bitmask for used aliases in aliases array + * @alias_pool: Pool of available client aliases * @i2c_nb: Notifier for remote client add & del events * @adapter: Array of adapters */ @@ -86,17 +100,54 @@ struct i2c_atr { struct mutex lock; int max_adapters; - size_t num_aliases; - const u16 *aliases; - /* Protects alias_use_mask */ - spinlock_t alias_mask_lock; - unsigned long *alias_use_mask; + struct i2c_atr_alias_pool *alias_pool; struct notifier_block i2c_nb; struct i2c_adapter *adapter[] __counted_by(max_adapters); }; +static struct i2c_atr_alias_pool *i2c_atr_alloc_alias_pool(size_t num_aliases) +{ + struct i2c_atr_alias_pool *alias_pool; + int ret; + + alias_pool = kzalloc(sizeof(*alias_pool), GFP_KERNEL); + if (!alias_pool) + return ERR_PTR(-ENOMEM); + + alias_pool->size = num_aliases; + + alias_pool->aliases = kcalloc(num_aliases, sizeof(*alias_pool->aliases), GFP_KERNEL); + if (!alias_pool->aliases) { + ret = -ENOMEM; + goto err_free_alias_pool; + } + + alias_pool->use_mask = bitmap_zalloc(num_aliases, GFP_KERNEL); + if (!alias_pool->use_mask) { + ret = -ENOMEM; + goto err_free_aliases; + } + + spin_lock_init(&alias_pool->lock); + + return alias_pool; + +err_free_aliases: + kfree(alias_pool->aliases); +err_free_alias_pool: + kfree(alias_pool); + return ERR_PTR(ret); +} + +static void i2c_atr_free_alias_pool(struct i2c_atr_alias_pool *alias_pool) +{ + bitmap_free(alias_pool->use_mask); + kfree(alias_pool->aliases); + kfree(alias_pool); +} + static struct i2c_atr_alias_pair * i2c_atr_find_mapping_by_addr(const struct list_head *list, u16 phys_addr) { @@ -259,44 +310,42 @@ static const struct i2c_lock_operations i2c_atr_lock_ops = { .unlock_bus = i2c_atr_unlock_bus, }; -static int i2c_atr_reserve_alias(struct i2c_atr *atr) +static int i2c_atr_reserve_alias(struct i2c_atr_alias_pool *alias_pool) { unsigned long idx; + u16 alias; - spin_lock(&atr->alias_mask_lock); + spin_lock(&alias_pool->lock); - idx = find_first_zero_bit(atr->alias_use_mask, atr->num_aliases); - if (idx >= atr->num_aliases) { - spin_unlock(&atr->alias_mask_lock); - dev_err(atr->dev, "failed to find a free alias\n"); + idx = find_first_zero_bit(alias_pool->use_mask, alias_pool->size); + if (idx >= alias_pool->size) { + spin_unlock(&alias_pool->lock); return -EBUSY; } - set_bit(idx, atr->alias_use_mask); + set_bit(idx, alias_pool->use_mask); - spin_unlock(&atr->alias_mask_lock); + alias = alias_pool->aliases[idx]; - return atr->aliases[idx]; + spin_unlock(&alias_pool->lock); + return alias; } -static void i2c_atr_release_alias(struct i2c_atr *atr, u16 alias) +static void i2c_atr_release_alias(struct i2c_atr_alias_pool *alias_pool, u16 alias) { unsigned int idx; - spin_lock(&atr->alias_mask_lock); + spin_lock(&alias_pool->lock); - for (idx = 0; idx < atr->num_aliases; ++idx) { - if (atr->aliases[idx] == alias) { - clear_bit(idx, atr->alias_use_mask); - spin_unlock(&atr->alias_mask_lock); + for (idx = 0; idx < alias_pool->size; ++idx) { + if (alias_pool->aliases[idx] == alias) { + clear_bit(idx, alias_pool->use_mask); + spin_unlock(&alias_pool->lock); return; } } - spin_unlock(&atr->alias_mask_lock); - - /* This should never happen */ - dev_warn(atr->dev, "Unable to find mapped alias\n"); + spin_unlock(&alias_pool->lock); } static int i2c_atr_attach_addr(struct i2c_adapter *adapter, @@ -308,9 +357,11 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, u16 alias; int ret; - ret = i2c_atr_reserve_alias(atr); - if (ret < 0) + ret = i2c_atr_reserve_alias(atr->alias_pool); + if (ret < 0) { + dev_err(atr->dev, "failed to find a free alias\n"); return ret; + } alias = ret; @@ -336,7 +387,7 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, err_free: kfree(c2a); err_release_alias: - i2c_atr_release_alias(atr, alias); + i2c_atr_release_alias(atr->alias_pool, alias); return ret; } @@ -357,7 +408,7 @@ static void i2c_atr_detach_addr(struct i2c_adapter *adapter, return; } - i2c_atr_release_alias(atr, c2a->alias); + i2c_atr_release_alias(atr->alias_pool, c2a->alias); dev_dbg(atr->dev, "chan%u: addr 0x%02x unmapped from alias 0x%02x\n", @@ -411,12 +462,11 @@ static int i2c_atr_bus_notifier_call(struct notifier_block *nb, static int i2c_atr_parse_alias_pool(struct i2c_atr *atr) { + struct i2c_atr_alias_pool *alias_pool; struct device *dev = atr->dev; - unsigned long *alias_use_mask; size_t num_aliases; unsigned int i; u32 *aliases32; - u16 *aliases16; int ret; ret = fwnode_property_count_u32(dev_fwnode(dev), "i2c-alias-pool"); @@ -428,12 +478,23 @@ static int i2c_atr_parse_alias_pool(struct i2c_atr *atr) num_aliases = ret; - if (!num_aliases) + alias_pool = i2c_atr_alloc_alias_pool(num_aliases); + if (IS_ERR(alias_pool)) { + ret = PTR_ERR(alias_pool); + dev_err(dev, "Failed to allocate alias pool, err %d\n", ret); + return ret; + } + + atr->alias_pool = alias_pool; + + if (!alias_pool->size) return 0; aliases32 = kcalloc(num_aliases, sizeof(*aliases32), GFP_KERNEL); - if (!aliases32) - return -ENOMEM; + if (!aliases32) { + ret = -ENOMEM; + goto err_free_alias_pool; + } ret = fwnode_property_read_u32_array(dev_fwnode(dev), "i2c-alias-pool", aliases32, num_aliases); @@ -443,43 +504,27 @@ static int i2c_atr_parse_alias_pool(struct i2c_atr *atr) goto err_free_aliases32; } - aliases16 = kcalloc(num_aliases, sizeof(*aliases16), GFP_KERNEL); - if (!aliases16) { - ret = -ENOMEM; - goto err_free_aliases32; - } - for (i = 0; i < num_aliases; i++) { if (!(aliases32[i] & 0xffff0000)) { - aliases16[i] = aliases32[i]; + alias_pool->aliases[i] = aliases32[i]; continue; } dev_err(dev, "Failed to parse 'i2c-alias-pool' property: I2C flags are not supported\n"); ret = -EINVAL; - goto err_free_aliases16; - } - - alias_use_mask = bitmap_zalloc(num_aliases, GFP_KERNEL); - if (!alias_use_mask) { - ret = -ENOMEM; - goto err_free_aliases16; + goto err_free_aliases32; } kfree(aliases32); - atr->num_aliases = num_aliases; - atr->aliases = aliases16; - atr->alias_use_mask = alias_use_mask; - - dev_dbg(dev, "i2c-alias-pool has %zu aliases", atr->num_aliases); + dev_dbg(dev, "i2c-alias-pool has %zu aliases", alias_pool->size); return 0; -err_free_aliases16: - kfree(aliases16); err_free_aliases32: kfree(aliases32); +err_free_alias_pool: + i2c_atr_free_alias_pool(alias_pool); return ret; } @@ -500,7 +545,6 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, return ERR_PTR(-ENOMEM); mutex_init(&atr->lock); - spin_lock_init(&atr->alias_mask_lock); atr->parent = parent; atr->dev = dev; @@ -520,13 +564,12 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, atr->i2c_nb.notifier_call = i2c_atr_bus_notifier_call; ret = bus_register_notifier(&i2c_bus_type, &atr->i2c_nb); if (ret) - goto err_free_aliases; + goto err_free_alias_pool; return atr; -err_free_aliases: - bitmap_free(atr->alias_use_mask); - kfree(atr->aliases); +err_free_alias_pool: + i2c_atr_free_alias_pool(atr->alias_pool); err_destroy_mutex: mutex_destroy(&atr->lock); kfree(atr); @@ -543,8 +586,7 @@ void i2c_atr_delete(struct i2c_atr *atr) WARN_ON(atr->adapter[i]); bus_unregister_notifier(&i2c_bus_type, &atr->i2c_nb); - bitmap_free(atr->alias_use_mask); - kfree(atr->aliases); + i2c_atr_free_alias_pool(atr->alias_pool); mutex_destroy(&atr->lock); kfree(atr); } From patchwork Mon Nov 18 10:13:05 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 844597 Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C43FE1922F2; 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arc=none smtp.client-ip=217.70.183.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="LxruCMwx" Received: by mail.gandi.net (Postfix) with ESMTPSA id BFA611BF207; Mon, 18 Nov 2024 10:13:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731924798; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iJgfCjnvNvvTwyd/QBAk+QnMdb9ttUUXMA4mNlEtL4o=; b=LxruCMwxnY1HAEI8M6hWwIMOXmCBVrpWOtOyw/YW7H0/QODQIhCUGRBxapUsuq0YtNV2LL EyMPFqr6F6kLsYA5Nf9GXcXqEfowLHWCAD0o8kVLiQu6BMawPsBZ2OSm3hDVEXLiNWey/F J1rB2lURBl7SBlwZ9BS5o2d/RB4+33tyf+QAEuZm1w+GjwPE+Pk45E56q2Kh/PC/G7wL/l ZI3gKjlfgp9HR/W46xip7oP98KLe1HSJlQ/+YPfOgRHDSbJJGMJixGPJuXCW2J+rwnfWuM WtK3p+mN/3JKmnQSFbJadi2kTYi1eYVR5ELEniRnDXhETcLowWarWsDLyUjsWg== From: Romain Gantois Date: Mon, 18 Nov 2024 11:13:05 +0100 Subject: [PATCH v2 6/9] i2c: rename field 'alias_list' of struct i2c_atr_chan to 'alias_pairs' Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241118-fpc202-v2-6-744e4f192a2d@bootlin.com> References: <20241118-fpc202-v2-0-744e4f192a2d@bootlin.com> In-Reply-To: <20241118-fpc202-v2-0-744e4f192a2d@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab , Linus Walleij , Bartosz Golaszewski Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, linux-gpio@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com The "alias_list" field of struct i2c_atr_chan describes translation table entries programmed in the ATR channel. This terminology will become more confusing when per-channel alias pool support is introduced, as struct i2c_atr_chan will gain a new field called "alias_pool", which will describe aliases which are available to the ATR channel. Rename the "alias_list" field to "alias_pairs" to clearly distinguish it from the future "alias_pool" field. No functional change is intended. Signed-off-by: Romain Gantois --- drivers/i2c/i2c-atr.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c index c873fe52288175151040a4c32e6ed07735586004..84d82c09708ae39cf5501a1fb67e8f2af2bb5446 100644 --- a/drivers/i2c/i2c-atr.c +++ b/drivers/i2c/i2c-atr.c @@ -56,7 +56,7 @@ struct i2c_atr_alias_pool { * @adap: The &struct i2c_adapter for the channel * @atr: The parent I2C ATR * @chan_id: The ID of this channel - * @alias_list: List of @struct i2c_atr_alias_pair containing the + * @alias_pairs: List of @struct i2c_atr_alias_pair containing the * assigned aliases * @orig_addrs_lock: Mutex protecting @orig_addrs * @orig_addrs: Buffer used to store the original addresses during transmit @@ -67,7 +67,7 @@ struct i2c_atr_chan { struct i2c_atr *atr; u32 chan_id; - struct list_head alias_list; + struct list_head alias_pairs; /* Lock orig_addrs during xfer */ struct mutex orig_addrs_lock; @@ -192,7 +192,7 @@ static int i2c_atr_map_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs, for (i = 0; i < num; i++) { chan->orig_addrs[i] = msgs[i].addr; - c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, + c2a = i2c_atr_find_mapping_by_addr(&chan->alias_pairs, msgs[i].addr); if (!c2a) { dev_err(atr->dev, "client 0x%02x not mapped!\n", @@ -262,7 +262,7 @@ static int i2c_atr_smbus_xfer(struct i2c_adapter *adap, u16 addr, struct i2c_adapter *parent = atr->parent; struct i2c_atr_alias_pair *c2a; - c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, addr); + c2a = i2c_atr_find_mapping_by_addr(&chan->alias_pairs, addr); if (!c2a) { dev_err(atr->dev, "client 0x%02x not mapped!\n", addr); return -ENXIO; @@ -380,7 +380,7 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, c2a->addr = addr; c2a->alias = alias; - list_add(&c2a->node, &chan->alias_list); + list_add(&c2a->node, &chan->alias_pairs); return 0; @@ -401,7 +401,7 @@ static void i2c_atr_detach_addr(struct i2c_adapter *adapter, atr->ops->detach_addr(atr, chan->chan_id, addr); - c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, addr); + c2a = i2c_atr_find_mapping_by_addr(&chan->alias_pairs, addr); if (!c2a) { /* This should never happen */ dev_warn(atr->dev, "Unable to find address mapping\n"); @@ -621,7 +621,7 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, chan->atr = atr; chan->chan_id = chan_id; - INIT_LIST_HEAD(&chan->alias_list); + INIT_LIST_HEAD(&chan->alias_pairs); mutex_init(&chan->orig_addrs_lock); snprintf(chan->adap.name, sizeof(chan->adap.name), "i2c-%d-atr-%d", From patchwork Mon Nov 18 10:13:06 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 844596 Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3235B19750B; Mon, 18 Nov 2024 10:13:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.201 ARC-Seal: i=1; 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dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="XWiEFEFp" Received: by mail.gandi.net (Postfix) with ESMTPSA id 515EF1BF20D; Mon, 18 Nov 2024 10:13:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731924799; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SjvACWeOBtIlxQ+9E7kITjN5s4TisAetZ11z5E/CII4=; b=XWiEFEFpZr8jfg3jiomMszjzPpmcAHtAR8/dZXhYhN0eQKTzty7jBnppgpvi1Mi124ysOb 3OlWAt3vsniYykvtR5UWtyhXM6HAkB5GHrFToXurNQQY1kZwr/Wz8JOeXFz8plgEkedotm rAWvg5wexiuwm6iJ3zDtbyAg088tpDGVwuVS15Gfs9LBbN4DjKAFCN5J2PhNtyIc/3gsa/ P6SskMtybg2LHRQzKJKbvHoi3xUFLjjakyCngblTdoG8tcXvNiU9q1J3FFnGYkb3fF5ZaU H6jFXvBXdUJyXhXcbboiFz/6N8RqtOUZbstfHc7lpzNRwQJlHrs2CXxGm+wW+Q== From: Romain Gantois Date: Mon, 18 Nov 2024 11:13:06 +0100 Subject: [PATCH v2 7/9] i2c: support per-channel ATR alias pools Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241118-fpc202-v2-7-744e4f192a2d@bootlin.com> References: <20241118-fpc202-v2-0-744e4f192a2d@bootlin.com> In-Reply-To: <20241118-fpc202-v2-0-744e4f192a2d@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab , Linus Walleij , Bartosz Golaszewski Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, linux-gpio@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com Some I2C address translators (ATRs) assign each of their remote peripheral aliases to a specific channel. To properly handle these devices, add support for having separate alias pools for each ATR channel. This is achieved by allowing callers of i2c_atr_add_adapter to pass an optional alias list. If present, this list will be used to populate the channel's alias pool. Otherwise, the common alias pool will be used. Signed-off-by: Romain Gantois --- drivers/i2c/i2c-atr.c | 68 ++++++++++++++++++++++++++++++------------- drivers/media/i2c/ds90ub913.c | 9 ++++-- drivers/media/i2c/ds90ub953.c | 9 ++++-- include/linux/i2c-atr.h | 34 ++++++++++++++++------ 4 files changed, 87 insertions(+), 33 deletions(-) diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c index 84d82c09708ae39cf5501a1fb67e8f2af2bb5446..f7c4d39ad3b48ad64be25b8462394e569aee57d4 100644 --- a/drivers/i2c/i2c-atr.c +++ b/drivers/i2c/i2c-atr.c @@ -37,6 +37,7 @@ struct i2c_atr_alias_pair { /** * struct i2c_atr_alias_pool - Pool of client aliases available for an ATR. * @size: Total number of aliases + * @shared: Indicates if this alias pool is shared by multiple channels * * @lock: Lock protecting @aliases and @use_mask * @aliases: Array of aliases, must hold exactly @size elements @@ -44,6 +45,7 @@ struct i2c_atr_alias_pair { */ struct i2c_atr_alias_pool { size_t size; + bool shared; /* Protects aliases and use_mask */ spinlock_t lock; @@ -58,6 +60,8 @@ struct i2c_atr_alias_pool { * @chan_id: The ID of this channel * @alias_pairs: List of @struct i2c_atr_alias_pair containing the * assigned aliases + * @alias_pool: Pool of available client aliases + * * @orig_addrs_lock: Mutex protecting @orig_addrs * @orig_addrs: Buffer used to store the original addresses during transmit * @orig_addrs_size: Size of @orig_addrs @@ -68,6 +72,7 @@ struct i2c_atr_chan { u32 chan_id; struct list_head alias_pairs; + struct i2c_atr_alias_pool *alias_pool; /* Lock orig_addrs during xfer */ struct mutex orig_addrs_lock; @@ -84,7 +89,7 @@ struct i2c_atr_chan { * @algo: The &struct i2c_algorithm for adapters * @lock: Lock for the I2C bus segment (see &struct i2c_lock_operations) * @max_adapters: Maximum number of adapters this I2C ATR can have - * @alias_pool: Pool of available client aliases + * @alias_pool: Optional common pool of available client aliases * @i2c_nb: Notifier for remote client add & del events * @adapter: Array of adapters */ @@ -357,7 +362,7 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, u16 alias; int ret; - ret = i2c_atr_reserve_alias(atr->alias_pool); + ret = i2c_atr_reserve_alias(chan->alias_pool); if (ret < 0) { dev_err(atr->dev, "failed to find a free alias\n"); return ret; @@ -387,7 +392,7 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, err_free: kfree(c2a); err_release_alias: - i2c_atr_release_alias(atr->alias_pool, alias); + i2c_atr_release_alias(chan->alias_pool, alias); return ret; } @@ -408,7 +413,7 @@ static void i2c_atr_detach_addr(struct i2c_adapter *adapter, return; } - i2c_atr_release_alias(atr->alias_pool, c2a->alias); + i2c_atr_release_alias(chan->alias_pool, c2a->alias); dev_dbg(atr->dev, "chan%u: addr 0x%02x unmapped from alias 0x%02x\n", @@ -469,14 +474,18 @@ static int i2c_atr_parse_alias_pool(struct i2c_atr *atr) u32 *aliases32; int ret; - ret = fwnode_property_count_u32(dev_fwnode(dev), "i2c-alias-pool"); - if (ret < 0) { - dev_err(dev, "Failed to count 'i2c-alias-pool' property: %d\n", - ret); - return ret; - } + if (!fwnode_property_present(dev_fwnode(dev), "i2c-alias-pool")) { + num_aliases = 0; + } else { + ret = fwnode_property_count_u32(dev_fwnode(dev), "i2c-alias-pool"); + if (ret < 0) { + dev_err(dev, "Failed to count 'i2c-alias-pool' property: %d\n", + ret); + return ret; + } - num_aliases = ret; + num_aliases = ret; + } alias_pool = i2c_atr_alloc_alias_pool(num_aliases); if (IS_ERR(alias_pool)) { @@ -592,15 +601,15 @@ void i2c_atr_delete(struct i2c_atr *atr) } EXPORT_SYMBOL_NS_GPL(i2c_atr_delete, I2C_ATR); -int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, - struct device *adapter_parent, - struct fwnode_handle *bus_handle) +int i2c_atr_add_adapter(struct i2c_atr *atr, struct i2c_atr_adap_desc *desc) { + struct fwnode_handle *bus_handle = desc->bus_handle; struct i2c_adapter *parent = atr->parent; + char symlink_name[ATR_MAX_SYMLINK_LEN]; struct device *dev = atr->dev; + u32 chan_id = desc->chan_id; struct i2c_atr_chan *chan; - char symlink_name[ATR_MAX_SYMLINK_LEN]; - int ret; + int ret, idx; if (chan_id >= atr->max_adapters) { dev_err(dev, "No room for more i2c-atr adapters\n"); @@ -616,8 +625,8 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, if (!chan) return -ENOMEM; - if (!adapter_parent) - adapter_parent = dev; + if (!desc->parent) + desc->parent = dev; chan->atr = atr; chan->chan_id = chan_id; @@ -629,7 +638,7 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, chan->adap.owner = THIS_MODULE; chan->adap.algo = &atr->algo; chan->adap.algo_data = chan; - chan->adap.dev.parent = adapter_parent; + chan->adap.dev.parent = desc->parent; chan->adap.retries = parent->retries; chan->adap.timeout = parent->timeout; chan->adap.quirks = parent->quirks; @@ -656,13 +665,26 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, fwnode_handle_put(atr_node); } + if (desc->num_aliases > 0) { + chan->alias_pool = i2c_atr_alloc_alias_pool(desc->num_aliases); + if (IS_ERR(chan->alias_pool)) { + ret = PTR_ERR(chan->alias_pool); + goto err_fwnode_put; + } + + for (idx = 0; idx < desc->num_aliases; idx++) + chan->alias_pool->aliases[idx] = desc->aliases[idx]; + } else { + chan->alias_pool = atr->alias_pool; + } + atr->adapter[chan_id] = &chan->adap; ret = i2c_add_adapter(&chan->adap); if (ret) { dev_err(dev, "failed to add atr-adapter %u (error=%d)\n", chan_id, ret); - goto err_fwnode_put; + goto err_free_alias_pool; } snprintf(symlink_name, sizeof(symlink_name), "channel-%u", @@ -679,6 +701,9 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, return 0; +err_free_alias_pool: + if (!chan->alias_pool->shared) + i2c_atr_free_alias_pool(chan->alias_pool); err_fwnode_put: fwnode_handle_put(dev_fwnode(&chan->adap.dev)); mutex_destroy(&chan->orig_addrs_lock); @@ -711,6 +736,9 @@ void i2c_atr_del_adapter(struct i2c_atr *atr, u32 chan_id) i2c_del_adapter(adap); + if (!chan->alias_pool->shared) + i2c_atr_free_alias_pool(chan->alias_pool); + atr->adapter[chan_id] = NULL; fwnode_handle_put(fwnode); diff --git a/drivers/media/i2c/ds90ub913.c b/drivers/media/i2c/ds90ub913.c index 8eed4a200fd89b5af1fc4578cb865bf1408acd76..1bb4efa44ede1267e15d29e0ce3965372bf3bb89 100644 --- a/drivers/media/i2c/ds90ub913.c +++ b/drivers/media/i2c/ds90ub913.c @@ -656,6 +656,7 @@ static int ub913_i2c_master_init(struct ub913_data *priv) static int ub913_add_i2c_adapter(struct ub913_data *priv) { struct device *dev = &priv->client->dev; + struct i2c_atr_adap_desc desc = { }; struct fwnode_handle *i2c_handle; int ret; @@ -663,8 +664,12 @@ static int ub913_add_i2c_adapter(struct ub913_data *priv) if (!i2c_handle) return 0; - ret = i2c_atr_add_adapter(priv->plat_data->atr, priv->plat_data->port, - dev, i2c_handle); + desc.chan_id = priv->plat_data->port; + desc.parent = dev; + desc.bus_handle = i2c_handle; + desc.num_aliases = 0; + + ret = i2c_atr_add_adapter(priv->plat_data->atr, &desc); fwnode_handle_put(i2c_handle); diff --git a/drivers/media/i2c/ds90ub953.c b/drivers/media/i2c/ds90ub953.c index 16f88db1498162cb795b1dcbe45bff90dd8ce431..e7cdb5d07a0378eab7aeeba36afdec319565c110 100644 --- a/drivers/media/i2c/ds90ub953.c +++ b/drivers/media/i2c/ds90ub953.c @@ -1103,6 +1103,7 @@ static int ub953_register_clkout(struct ub953_data *priv) static int ub953_add_i2c_adapter(struct ub953_data *priv) { struct device *dev = &priv->client->dev; + struct i2c_atr_adap_desc desc = { }; struct fwnode_handle *i2c_handle; int ret; @@ -1110,8 +1111,12 @@ static int ub953_add_i2c_adapter(struct ub953_data *priv) if (!i2c_handle) return 0; - ret = i2c_atr_add_adapter(priv->plat_data->atr, priv->plat_data->port, - dev, i2c_handle); + desc.chan_id = priv->plat_data->port; + desc.parent = dev; + desc.bus_handle = i2c_handle; + desc.num_aliases = 0; + + ret = i2c_atr_add_adapter(priv->plat_data->atr, &desc); fwnode_handle_put(i2c_handle); diff --git a/include/linux/i2c-atr.h b/include/linux/i2c-atr.h index 14c1f9175c0db6a8a9c6ef5d771ae68361132a76..1c3a5bcd939fc56f4a6ca1b6a5cc0ac2c17083b7 100644 --- a/include/linux/i2c-atr.h +++ b/include/linux/i2c-atr.h @@ -36,6 +36,29 @@ struct i2c_atr_ops { u16 addr); }; +/** + * struct i2c_atr_adap_desc - An ATR downstream bus descriptor + * @chan_id: Index of the new adapter (0 .. max_adapters-1). This value is + * passed to the callbacks in `struct i2c_atr_ops`. + * @parent: The device used as the parent of the new i2c adapter, or NULL + * to use the i2c-atr device as the parent. + * @bus_handle: The fwnode handle that points to the adapter's i2c + * peripherals, or NULL. + * @num_aliases: The number of aliases in this adapter's private alias pool. Set + * to zero if this adapter uses the ATR's global alias pool. + * @aliases: An optional array of private aliases used by the adapter + * instead of the ATR's global pool of aliases. Must contain + * exactly num_aliases entries if num_aliases > 0, is ignored + * otherwise. + */ +struct i2c_atr_adap_desc { + u32 chan_id; + struct device *parent; + struct fwnode_handle *bus_handle; + size_t num_aliases; + u16 *aliases; +}; + /** * i2c_atr_new() - Allocate and initialize an I2C ATR helper. * @parent: The parent (upstream) adapter @@ -65,12 +88,7 @@ void i2c_atr_delete(struct i2c_atr *atr); /** * i2c_atr_add_adapter - Create a child ("downstream") I2C bus. * @atr: The I2C ATR - * @chan_id: Index of the new adapter (0 .. max_adapters-1). This value is - * passed to the callbacks in `struct i2c_atr_ops`. - * @adapter_parent: The device used as the parent of the new i2c adapter, or NULL - * to use the i2c-atr device as the parent. - * @bus_handle: The fwnode handle that points to the adapter's i2c - * peripherals, or NULL. + * @desc: An ATR adapter descriptor * * After calling this function a new i2c bus will appear. Adding and removing * devices on the downstream bus will result in calls to the @@ -85,9 +103,7 @@ void i2c_atr_delete(struct i2c_atr *atr); * * Return: 0 on success, a negative error code otherwise. */ -int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, - struct device *adapter_parent, - struct fwnode_handle *bus_handle); +int i2c_atr_add_adapter(struct i2c_atr *atr, struct i2c_atr_adap_desc *desc); /** * i2c_atr_del_adapter - Remove a child ("downstream") I2C bus added by From patchwork Mon Nov 18 10:13:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 844595 Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A89241993B9; Mon, 18 Nov 2024 10:13:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731924806; cv=none; b=R5+j6AgsRguxqE457wdiNxnTJm1+DBy7gopY3OSKQGbyHWDt76WNjZasO73dhf7GIR4owE4OEHIGb1+Qe/p7uUmAzpegYFKFyZx7uERpxdwMeWKTSrDVsjGlbskZ3AMj+DnPcD6gB1AmDeIB6PMe+Bx9mtiSrW5/v9W3UQsaRnY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731924806; c=relaxed/simple; bh=DMXNwZOe7VTP6nLjoy8Qtj0hYvjnz5ZKwYelMecb2rg=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=VRYXkHgcFuKxz+GxC0r0hUPtwQC1xrdjW5BtyJPyyOEdCUJPYA/CI0vKuQfcsN8Ng/pDbmQcJsJpvt0+urUpNLJTNyniJ0H/LmfaqG6RV0+qTKr0Kef4H/7nDEDyvo3UkJur2teA+RTBaQJMktXpBMxpJtT1F6qd2RsDbTImdrQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=dhw20Mna; arc=none smtp.client-ip=217.70.183.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="dhw20Mna" Received: by mail.gandi.net (Postfix) with ESMTPSA id DC45E1BF206; Mon, 18 Nov 2024 10:13:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731924802; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8zQ60HZDSNEpSw7YA2yv5ZjhW3bIxi5XEA+lougsw9U=; b=dhw20Mnaaau7Y8zjMKF8X7cCcmJFhhdVF6ZxW7EeHzKCqQ8lR6GsidSVp81co/gN5+6E8G smfVCrYUyjUiaok6RSIS5zKhO3ciaYNnVfJ3cwbeC+FNiVSrp6LxK9Ch+THcq9vBz4rh+R M/C0m8eA/2X6OCV2gqQ9n4Im7+4hEpkFqMYN2ay1A4Akfko2bLmHcE2chdBsBPuNLp7GLf Txzz9XUySLwlWRlsl1P/0dau0R0S2xY7UOl/vIr6o0JlQOopv0N74j1X1rsf0pkAxsVCVl tso2635HqJfaBwoAJePNP12/hYmSQD//51/2Ea7Um2pM4+8xu/iqEk03jNtJZg== From: Romain Gantois Date: Mon, 18 Nov 2024 11:13:08 +0100 Subject: [PATCH v2 9/9] misc: add FPC202 dual port controller driver Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241118-fpc202-v2-9-744e4f192a2d@bootlin.com> References: <20241118-fpc202-v2-0-744e4f192a2d@bootlin.com> In-Reply-To: <20241118-fpc202-v2-0-744e4f192a2d@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab , Linus Walleij , Bartosz Golaszewski Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, linux-gpio@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com The TI FPC202 dual port controller serves as a low- speed signal aggregator for common port types such as SFP, QSFP, Mini-SAS HD, and others. It aggregates GPIO and I2C signals across two downstream ports, acting as both a GPIO controller and an I2C address translator for up to two logical devices per port. Signed-off-by: Romain Gantois --- MAINTAINERS | 1 + drivers/misc/Kconfig | 11 ++ drivers/misc/Makefile | 1 + drivers/misc/ti_fpc202.c | 440 +++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 453 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index 8e702cefd2070790330eebf6d2a2b592cadb682d..a9e357b7a1ff95e24b45619eb5521a4fc242251b 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -23186,6 +23186,7 @@ M: Romain Gantois L: linux-kernel@vger.kernel.org S: Maintained F: Documentation/devicetree/bindings/misc/ti,fpc202.yaml +F: drivers/misc/ti_fpc202.c TI FPD-LINK DRIVERS M: Tomi Valkeinen diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 3fe7e2a9bd294da562cf553d958772dcb49bbc89..2549989422c5b1a67a886290efcd692c0835c7e1 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -114,6 +114,17 @@ config RPMB If unsure, select N. +config TI_FPC202 + tristate "TI FPC202 Dual Port Controller" + select GPIOLIB + depends on I2C_ATR + help + If you say yes here you get support for the Texas Instruments FPC202 + Dual Port Controller. + + This driver can also be built as a module. If so, the module will be + called fpc202. + config TIFM_CORE tristate "TI Flash Media interface support" depends on PCI diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index a9f94525e1819d5d7eed4937ce1d50b2875ee71b..d0b7a1b96619b3125d1455d40268040e0764b341 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -12,6 +12,7 @@ obj-$(CONFIG_ATMEL_SSC) += atmel-ssc.o obj-$(CONFIG_DUMMY_IRQ) += dummy-irq.o obj-$(CONFIG_ICS932S401) += ics932s401.o obj-$(CONFIG_LKDTM) += lkdtm/ +obj-$(CONFIG_TI_FPC202) += ti_fpc202.o obj-$(CONFIG_TIFM_CORE) += tifm_core.o obj-$(CONFIG_TIFM_7XX1) += tifm_7xx1.o obj-$(CONFIG_PHANTOM) += phantom.o diff --git a/drivers/misc/ti_fpc202.c b/drivers/misc/ti_fpc202.c new file mode 100644 index 0000000000000000000000000000000000000000..5ea2ab358098fdabd3c6372b581724bf20265400 --- /dev/null +++ b/drivers/misc/ti_fpc202.c @@ -0,0 +1,440 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ti_fpc202.c - FPC202 Dual Port Controller driver + * + * Copyright (C) 2024 Bootlin + * + */ + +#include +#include +#include +#include +#include +#include + +#define FPC202_NUM_PORTS 2 +#define FPC202_ALIASES_PER_PORT 2 + +/* + * GPIO: port mapping + * + * 0: P0_S0_IN_A + * 1: P0_S1_IN_A + * 2: P1_S0_IN_A + * 3: P1_S1_IN_A + * 4: P0_S0_IN_B + * ... + * 8: P0_S0_IN_C + * ... + * 12: P0_S0_OUT_A + * ... + * 16: P0_S0_OUT_B + * ... + * 19: P1_S1_OUT_B + * + */ + +#define FPC202_GPIO_COUNT 20 +#define FPC202_GPIO_P0_S0_IN_B 4 +#define FPC202_GPIO_P0_S0_OUT_A 12 + +#define FPC202_REG_IN_A_INT 0x6 +#define FPC202_REG_IN_C_IN_B 0x7 +#define FPC202_REG_OUT_A_OUT_B 0x8 + +#define FPC202_REG_OUT_A_OUT_B_VAL 0xa + +#define FPC202_REG_MOD_DEV(port, dev) (0xb4 + ((port) * 4) + (dev)) +#define FPC202_REG_AUX_DEV(port, dev) (0xb6 + ((port) * 4) + (dev)) + +/* + * The FPC202 doesn't support turning off address translation on a single port. + * So just set an invalid I2C address as the translation target when no client + * address is attached. + */ +#define FPC202_REG_DEV_INVALID 0 + +/* Even aliases are assigned to device 0 and odd aliases to device 1 */ +#define fpc202_dev_num_from_alias(alias) ((alias) % 2) + +struct fpc202_priv { + struct i2c_client *client; + struct i2c_atr *atr; + struct gpio_desc *en_gpio; + struct gpio_chip gpio; + + /* Lock REG_MOD/AUX_DEV and addr_caches during attach/detach */ + struct mutex reg_dev_lock; + + /* Cached device addresses for both ports and their devices */ + u8 addr_caches[2][2]; +}; + +static void fpc202_fill_alias_table(struct i2c_client *client, u16 *aliases, int port_id) +{ + u16 first_alias; + int i; + + /* + * There is a predefined list of aliases for each FPC202 I2C + * self-address. This allows daisy-chained FPC202 units to + * automatically take on different sets of aliases. + * Each port of an FPC202 unit is assigned two aliases from this list. + */ + first_alias = 0x10 + 4 * port_id + 8 * ((u16)client->addr - 2); + + for (i = 0; i < FPC202_ALIASES_PER_PORT; i++) + aliases[i] = first_alias + i; +} + +static int fpc202_gpio_get_dir(int offset) +{ + return offset < FPC202_GPIO_P0_S0_OUT_A ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT; +} + +static int fpc202_read(struct fpc202_priv *priv, u8 reg) +{ + int val; + + val = i2c_smbus_read_byte_data(priv->client, reg); + return val; +} + +static int fpc202_write(struct fpc202_priv *priv, u8 reg, u8 value) +{ + return i2c_smbus_write_byte_data(priv->client, reg, value); +} + +static void fpc202_set_enable(struct fpc202_priv *priv, int enable) +{ + if (!priv->en_gpio) + return; + + gpiod_set_value(priv->en_gpio, enable); +} + +static void fpc202_gpio_set(struct gpio_chip *chip, unsigned int offset, + int value) +{ + struct fpc202_priv *priv = gpiochip_get_data(chip); + int ret; + u8 val; + + if (fpc202_gpio_get_dir(offset) == GPIO_LINE_DIRECTION_IN) + return; + + ret = fpc202_read(priv, FPC202_REG_OUT_A_OUT_B_VAL); + if (ret < 0) { + dev_err(&priv->client->dev, "Failed to set GPIO %d value! err %d\n", offset, ret); + return; + } + + val = (u8)ret; + + if (value) + val |= BIT(offset - FPC202_GPIO_P0_S0_OUT_A); + else + val &= ~BIT(offset - FPC202_GPIO_P0_S0_OUT_A); + + fpc202_write(priv, FPC202_REG_OUT_A_OUT_B_VAL, val); +} + +static int fpc202_gpio_get(struct gpio_chip *chip, unsigned int offset) +{ + struct fpc202_priv *priv = gpiochip_get_data(chip); + u8 reg, bit; + int ret; + + if (offset < FPC202_GPIO_P0_S0_IN_B) { + reg = FPC202_REG_IN_A_INT; + bit = BIT(4 + offset); + } else if (offset < FPC202_GPIO_P0_S0_OUT_A) { + reg = FPC202_REG_IN_C_IN_B; + bit = BIT(offset - FPC202_GPIO_P0_S0_IN_B); + } else { + reg = FPC202_REG_OUT_A_OUT_B_VAL; + bit = BIT(offset - FPC202_GPIO_P0_S0_OUT_A); + } + + ret = fpc202_read(priv, reg); + if (ret < 0) + return ret; + + return !!(((u8)ret) & bit); +} + +static int fpc202_gpio_direction_input(struct gpio_chip *chip, unsigned int offset) +{ + if (fpc202_gpio_get_dir(offset) == GPIO_LINE_DIRECTION_OUT) + return -EINVAL; + + return 0; +} + +static int fpc202_gpio_direction_output(struct gpio_chip *chip, unsigned int offset, + int value) +{ + struct fpc202_priv *priv = gpiochip_get_data(chip); + int ret; + u8 val; + + if (fpc202_gpio_get_dir(offset) == GPIO_LINE_DIRECTION_IN) + return -EINVAL; + + fpc202_gpio_set(chip, offset, value); + + ret = fpc202_read(priv, FPC202_REG_OUT_A_OUT_B); + if (ret < 0) + return ret; + + val = (u8)ret | BIT(offset - FPC202_GPIO_P0_S0_OUT_A); + + return fpc202_write(priv, FPC202_REG_OUT_A_OUT_B, val); +} + +/* + * Set the translation table entry associated with a port and device number. + * + * Each downstream port of the FPC202 has two fixed aliases corresponding to + * device numbers 0 and 1. If one of these aliases is found in an incoming I2C + * transfer, it will be translated to the address given by the corresponding + * translation table entry. + */ +static int fpc202_write_dev_addr(struct fpc202_priv *priv, u32 port_id, int dev_num, u16 addr) +{ + int ret, reg_mod, reg_aux; + u8 val; + + mutex_lock(&priv->reg_dev_lock); + + reg_mod = FPC202_REG_MOD_DEV(port_id, dev_num); + reg_aux = FPC202_REG_AUX_DEV(port_id, dev_num); + val = addr & 0x7f; + + ret = fpc202_write(priv, reg_mod, val); + if (ret) + goto out_unlock; + + /* + * The FPC202 datasheet is unclear about the role of the AUX registers. + * Empirically, writing to them as well seems to be necessary for + * address translation to function properly. + */ + ret = fpc202_write(priv, reg_aux, val); + + priv->addr_caches[port_id][dev_num] = val; + +out_unlock: + mutex_unlock(&priv->reg_dev_lock); + return ret; +} + +static int fpc202_attach_addr(struct i2c_atr *atr, u32 chan_id, + u16 addr, u16 alias) +{ + struct fpc202_priv *priv = i2c_atr_get_driver_data(atr); + + dev_dbg(&priv->client->dev, "attaching address 0x%02x to alias 0x%02x\n", addr, alias); + + return fpc202_write_dev_addr(priv, chan_id, fpc202_dev_num_from_alias(alias), addr); +} + +static void fpc202_detach_addr(struct i2c_atr *atr, u32 chan_id, + u16 addr) +{ + struct fpc202_priv *priv = i2c_atr_get_driver_data(atr); + int dev_num, reg_mod, val; + + for (dev_num = 0; dev_num < 2; dev_num++) { + reg_mod = FPC202_REG_MOD_DEV(chan_id, dev_num); + + mutex_lock(&priv->reg_dev_lock); + + val = priv->addr_caches[chan_id][dev_num]; + + mutex_unlock(&priv->reg_dev_lock); + + if (val < 0) { + dev_err(&priv->client->dev, "failed to read register 0x%x while detaching address 0x%02x\n", + reg_mod, addr); + return; + } + + if (val == (addr & 0x7f)) { + fpc202_write_dev_addr(priv, chan_id, dev_num, FPC202_REG_DEV_INVALID); + return; + } + } +} + +static const struct i2c_atr_ops fpc202_atr_ops = { + .attach_addr = fpc202_attach_addr, + .detach_addr = fpc202_detach_addr, +}; + +static int fpc202_probe_port(struct fpc202_priv *priv, int port_id) +{ + u16 aliases[FPC202_ALIASES_PER_PORT] = { }; + struct device *dev = &priv->client->dev; + struct i2c_atr_adap_desc desc = { }; + struct device_node *i2c_handle; + u32 addr = -1; + int ret = 0; + + if (port_id > 2) { + dev_err(dev, "port ID %d is out of range!\n", port_id); + return -EINVAL; + } + + for_each_child_of_node(dev->of_node, i2c_handle) { + ret = of_property_read_u32(i2c_handle, "reg", &addr); + if (ret) { + dev_err(dev, "failed to read 'reg' property of child node, err %d\n", ret); + return ret; + } + + if (addr == port_id) + break; + } + + if (addr != port_id) { + dev_err(dev, "failed to find port node %d, err %d\n", port_id, ret); + return -EINVAL; + } + + desc.chan_id = port_id; + desc.parent = dev; + desc.bus_handle = of_node_to_fwnode(i2c_handle); + desc.num_aliases = FPC202_ALIASES_PER_PORT; + + fpc202_fill_alias_table(priv->client, aliases, port_id); + desc.aliases = aliases; + + ret = i2c_atr_add_adapter(priv->atr, &desc); + if (ret) + return ret; + + of_node_put(i2c_handle); + + ret = fpc202_write_dev_addr(priv, port_id, 0, FPC202_REG_DEV_INVALID); + if (ret) + return ret; + + return fpc202_write_dev_addr(priv, port_id, 1, FPC202_REG_DEV_INVALID); +} + +static int fpc202_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct fpc202_priv *priv; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + mutex_init(&priv->reg_dev_lock); + + priv->client = client; + i2c_set_clientdata(client, priv); + + priv->en_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_HIGH); + if (IS_ERR(priv->en_gpio)) { + ret = PTR_ERR(priv->en_gpio); + dev_err(dev, "failed to fetch enable GPIO! err %d\n", ret); + goto destroy_mutex; + } + + priv->gpio.label = "gpio-fpc202"; + priv->gpio.base = -1; + priv->gpio.direction_input = fpc202_gpio_direction_input; + priv->gpio.direction_output = fpc202_gpio_direction_output; + priv->gpio.set = fpc202_gpio_set; + priv->gpio.get = fpc202_gpio_get; + priv->gpio.ngpio = FPC202_GPIO_COUNT; + priv->gpio.parent = dev; + priv->gpio.owner = THIS_MODULE; + + ret = gpiochip_add_data(&priv->gpio, priv); + if (ret) { + priv->gpio.parent = NULL; + dev_err(dev, "failed to add gpiochip err %d", ret); + goto disable_gpio; + } + + priv->atr = i2c_atr_new(client->adapter, dev, &fpc202_atr_ops, 2, I2C_ATR_FLAG_DYNAMIC_C2A); + if (IS_ERR(priv->atr)) { + ret = PTR_ERR(priv->atr); + dev_err(dev, "failed to create i2c atr err %d", ret); + goto disable_gpio; + } + + i2c_atr_set_driver_data(priv->atr, priv); + + ret = fpc202_probe_port(priv, 0); + if (ret) { + dev_err(dev, "Failed to probe port 0, err %d\n", ret); + goto delete_atr; + } + + ret = fpc202_probe_port(priv, 1); + if (ret) { + dev_err(dev, "Failed to probe port 1, err %d\n", ret); + goto unregister_port; + } + + dev_info(&client->dev, "%s FPC202 Dual Port controller found\n", client->name); + + goto out; + +unregister_port: + i2c_atr_del_adapter(priv->atr, 0); +delete_atr: + i2c_atr_delete(priv->atr); +disable_gpio: + fpc202_set_enable(priv, 0); + gpiochip_remove(&priv->gpio); +destroy_mutex: + mutex_destroy(&priv->reg_dev_lock); +out: + return ret; +} + +static void fpc202_remove(struct i2c_client *client) +{ + struct fpc202_priv *priv = i2c_get_clientdata(client); + int port_id; + + for (port_id = 0; port_id < FPC202_NUM_PORTS; port_id++) + i2c_atr_del_adapter(priv->atr, port_id); + + mutex_destroy(&priv->reg_dev_lock); + + i2c_atr_delete(priv->atr); + + fpc202_set_enable(priv, 0); + gpiochip_remove(&priv->gpio); +} + +static const struct of_device_id fpc202_of_match[] = { + { .compatible = "ti,fpc202" }, + {} +}; +MODULE_DEVICE_TABLE(of, fpc202_of_match); + +static struct i2c_driver fpc202_driver = { + .driver = { + .name = "fpc202", + .of_match_table = fpc202_of_match, + }, + .probe = fpc202_probe, + .remove = fpc202_remove, +}; + +module_i2c_driver(fpc202_driver); + +MODULE_AUTHOR("Romain Gantois "); +MODULE_DESCRIPTION("TI FPC202 Dual Port Controller driver"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(I2C_ATR);