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Thu, 10 Oct 2024 02:10:34 -0700 (PDT) From: Bartosz Golaszewski Date: Thu, 10 Oct 2024 11:10:23 +0200 Subject: [PATCH v2 2/6] gpio: cdev: prepare gpio_desc_to_lineinfo() for being called from atomic Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241010-gpio-notify-in-kernel-events-v2-2-b560411f7c59@linaro.org> References: <20241010-gpio-notify-in-kernel-events-v2-0-b560411f7c59@linaro.org> In-Reply-To: <20241010-gpio-notify-in-kernel-events-v2-0-b560411f7c59@linaro.org> To: Linus Walleij , Bartosz Golaszewski , Kent Gibson Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Bartosz Golaszewski X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2675; i=bartosz.golaszewski@linaro.org; h=from:subject:message-id; bh=hJXOR0yJYCJfsL+TmH/jw016J3uAhH62oK/KOdi1k0I=; b=owEBbQKS/ZANAwAKARGnLqAUcddyAcsmYgBnB5oGjSwEYXib+XZ21p/SuNORc1oC0p1EE0/8J drAnwmFJVKJAjMEAAEKAB0WIQQWnetsC8PEYBPSx58Rpy6gFHHXcgUCZweaBgAKCRARpy6gFHHX cutVD/9gzcyiCBHbwNEqZFcoHr14MA1mOkJnkB2Rp7I2Y8AKcoBpD69jha+emJQO5FcolxravSe /8w/w6VAKG9oyG99STzDtyF+bBgT5uoNPDbgGfU82WqKKgH+6mnbOFvZyEXmFovpkhDtcU3SCwN DLb1Ar3klfSexGW1k1pt1dVThBx2kmexzeCHgtFFaqTJksXPjyCp+BGIRjJXaW5BdoKTUlRmL6J Y9j5jZkMGNKPgFohUp9+5W6hy2Qch4dIJh9iOBS/VAX6KHboD+1VM7kjTKUBPX7EsQUzcO4BYCO Tqnn+cFBzb3Kf/iCDj6zT/422IGOK8IWVOnNnkROXYpv+Kr8Ng0mQqYaiupGxRu4IYy2uTYqWJM si7GpoGbrmf2DL/84lb3cLptpOeycWGKHVlRx+QkQ5b40nHVrePDh8uWTicxNqPgxDKmAHsn+Dv s3ozdcWPGRDld8ncE99rx1JHkAlILg9tiDfIy5a0BakXLbsrIVFUw45j/Ap6WienPNSYC4gEqZZ V/SgXUXVdNHwz0eUCjCikEAWoMY4wl5XmXSqRPdWnU0RbuKMBN5ALUjyU7rx95YZslhp1svKK08 qNLi0Zozzo7YZAZFc9ZfbG3vRIPKu5Lrc4VEpnBG8I2gpdvZlVO5hCjKFOcX1+9ESx4955RBHTZ Vu45kdUpjcIod1w== X-Developer-Key: i=bartosz.golaszewski@linaro.org; a=openpgp; fpr=169DEB6C0BC3C46013D2C79F11A72EA01471D772 From: Bartosz Golaszewski In order to prepare gpio_desc_to_lineinfo() to being called from atomic context, add a new argument - bool atomic - which, if set, indicates that no sleeping functions must be called (currently: only pinctrl_gpio_can_use_line()). Signed-off-by: Bartosz Golaszewski --- drivers/gpio/gpiolib-cdev.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index b0050250ac3a..8c48a53b4fa8 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -2361,7 +2361,7 @@ static void gpio_v2_line_info_changed_to_v1( #endif /* CONFIG_GPIO_CDEV_V1 */ static void gpio_desc_to_lineinfo(struct gpio_desc *desc, - struct gpio_v2_line_info *info) + struct gpio_v2_line_info *info, bool atomic) { unsigned long dflags; const char *label; @@ -2402,9 +2402,13 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc, test_bit(FLAG_USED_AS_IRQ, &dflags) || test_bit(FLAG_EXPORT, &dflags) || test_bit(FLAG_SYSFS, &dflags) || - !gpiochip_line_is_valid(guard.gc, info->offset) || - !pinctrl_gpio_can_use_line(guard.gc, info->offset)) + !gpiochip_line_is_valid(guard.gc, info->offset)) info->flags |= GPIO_V2_LINE_FLAG_USED; + + if (!atomic) { + if (!pinctrl_gpio_can_use_line(guard.gc, info->offset)) + info->flags |= GPIO_V2_LINE_FLAG_USED; + } if (test_bit(FLAG_IS_OUT, &dflags)) info->flags |= GPIO_V2_LINE_FLAG_OUTPUT; @@ -2502,7 +2506,7 @@ static int lineinfo_get_v1(struct gpio_chardev_data *cdev, void __user *ip, return -EBUSY; } - gpio_desc_to_lineinfo(desc, &lineinfo_v2); + gpio_desc_to_lineinfo(desc, &lineinfo_v2, false); gpio_v2_line_info_to_v1(&lineinfo_v2, &lineinfo); if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) { @@ -2539,7 +2543,7 @@ static int lineinfo_get(struct gpio_chardev_data *cdev, void __user *ip, if (test_and_set_bit(lineinfo.offset, cdev->watched_lines)) return -EBUSY; } - gpio_desc_to_lineinfo(desc, &lineinfo); + gpio_desc_to_lineinfo(desc, &lineinfo, false); supinfo_to_lineinfo(desc, &lineinfo); if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) { @@ -2632,7 +2636,7 @@ static int lineinfo_changed_notify(struct notifier_block *nb, memset(&chg, 0, sizeof(chg)); chg.event_type = action; chg.timestamp_ns = ktime_get_ns(); - gpio_desc_to_lineinfo(desc, &chg.info); + gpio_desc_to_lineinfo(desc, &chg.info, false); 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Thu, 10 Oct 2024 02:10:37 -0700 (PDT) From: Bartosz Golaszewski Date: Thu, 10 Oct 2024 11:10:25 +0200 Subject: [PATCH v2 4/6] gpio: cdev: put emitting the line state events on a workqueue Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241010-gpio-notify-in-kernel-events-v2-4-b560411f7c59@linaro.org> References: <20241010-gpio-notify-in-kernel-events-v2-0-b560411f7c59@linaro.org> In-Reply-To: <20241010-gpio-notify-in-kernel-events-v2-0-b560411f7c59@linaro.org> To: Linus Walleij , Bartosz Golaszewski , Kent Gibson Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Bartosz Golaszewski X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=4357; i=bartosz.golaszewski@linaro.org; h=from:subject:message-id; bh=sCvTb92VsU9o5sQdk/sTByAevcKbdTEudD1FU5KTG6Q=; b=owEBbQKS/ZANAwAKARGnLqAUcddyAcsmYgBnB5oHslqxMHergOZ85ymfnNVnjvhx3UNOSbjhy 2Tk58ON3MaJAjMEAAEKAB0WIQQWnetsC8PEYBPSx58Rpy6gFHHXcgUCZweaBwAKCRARpy6gFHHX cpHhD/9U+MxzygvDhzTtOpl7hxtef7JseBNg7YFZUWg3KraN6xZf2ymhT7rzcDY+X4/yhxSGLm2 beutzqT3WHKrBUJ+uNbipqgdi3i+W8CjU/pr1Ok1KWwjqPTJiWtWEtWnrbTA55n1wLAYiKPxLNj Gv8GmuK66jlM1tlJSo/FZkpU6dTi40qQqg4FGaJGci7CWj4HsB6rB6sh0Sqii40nqLXUsQbLA++ hzAL+Et9JLk1akIAWA9y3h4Dq8+lVuntGVWzJAkqvbIm5xbJL6xKXHjXKBqx/kNyGtuOcSnsIUQ Pknm5X74ARS926scOPe6N7KLI54Pu3ib/B+SD+aTKoT9VIRHRnS7fwWgfwQA/QN5s1G/mIfiqwZ zcfBu5hT+ct6hlZTB25+n39OUwmUQvI/YmN2liHsLwjtGg5fKlwpojb351lJQxohmnhf0TjsWKz 4UXNDuwnR4LmXIlRA2qY7SR5fr5AF4/3zBY/CAMTBslwDKbSKQUhUFbxFRlWw+JVbJvciWPJOrF vxuUQQq24KLXzoB6urAc1t6jr3uamnw92u0NKLcH1IiCl2YLwQEV5qWB1mto8PKbUtX+0tm/mKa Dcpp10U8G5Z/vkJpGSdCqk3mvjVQHpgEmzilP68dMZTtoixEh2UdHHi0G1FF7/lKFVTGsGi+gi0 AOz2k5r6wbw5zeQ== X-Developer-Key: i=bartosz.golaszewski@linaro.org; a=openpgp; fpr=169DEB6C0BC3C46013D2C79F11A72EA01471D772 From: Bartosz Golaszewski In order to allow line state notifications to be emitted from atomic context (for instance: from gpiod_direction_input/output()), we must stop calling any sleeping functions in lineinfo_changed_notify(). To that end let's use the new workqueue. Let's atomically allocate small structures containing the required data and fill it with information immediately upon being notified about the change except for the pinctrl state which will be retrieved later from process context. We can pretty reliably do this as pin functions are typically set once per boot. Let's make sure to bump the reference count of GPIO device and the GPIO character device file descriptor to keep both alive until the event was queued. Signed-off-by: Bartosz Golaszewski --- drivers/gpio/gpiolib-cdev.c | 72 +++++++++++++++++++++++++++++++++++++-------- 1 file changed, 60 insertions(+), 12 deletions(-) diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index dec6c9a6005f..2677134b52cd 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -2451,6 +2451,7 @@ struct gpio_chardev_data { #ifdef CONFIG_GPIO_CDEV_V1 atomic_t watch_abi_version; #endif + struct file *fp; }; static int chipinfo_get(struct gpio_chardev_data *cdev, void __user *ip) @@ -2621,29 +2622,75 @@ static long gpio_ioctl_compat(struct file *file, unsigned int cmd, } #endif +struct lineinfo_changed_ctx { + struct work_struct work; + struct gpio_v2_line_info_changed chg; + struct gpio_device *gdev; + struct gpio_chardev_data *cdev; +}; + +static void lineinfo_changed_func(struct work_struct *work) +{ + struct lineinfo_changed_ctx *ctx = + container_of(work, struct lineinfo_changed_ctx, work); + struct gpio_chip *gc; + int ret; + + scoped_guard(srcu, &ctx->gdev->srcu) { + gc = srcu_dereference(ctx->gdev->chip, &ctx->gdev->srcu); + if (!gc) + return; + + /* + * We're doing this late because it's a sleeping function. Pin + * functions are in general much more static and while it's not + * 100% bullet-proof, it's good enough for most cases. + */ + if (!pinctrl_gpio_can_use_line(gc, ctx->chg.info.offset)) + ctx->chg.info.flags |= GPIO_V2_LINE_FLAG_USED; + } + + ret = kfifo_in_spinlocked(&ctx->cdev->events, &ctx->chg, 1, + &ctx->cdev->wait.lock); + if (ret) + wake_up_poll(&ctx->cdev->wait, EPOLLIN); + else + pr_debug_ratelimited("lineinfo event FIFO is full - event dropped\n"); + + gpio_device_put(ctx->gdev); + fput(ctx->cdev->fp); + kfree(ctx); +} + static int lineinfo_changed_notify(struct notifier_block *nb, unsigned long action, void *data) { struct gpio_chardev_data *cdev = container_of(nb, struct gpio_chardev_data, lineinfo_changed_nb); - struct gpio_v2_line_info_changed chg; + struct lineinfo_changed_ctx *ctx; struct gpio_desc *desc = data; - int ret; if (!test_bit(gpio_chip_hwgpio(desc), cdev->watched_lines)) return NOTIFY_DONE; - memset(&chg, 0, sizeof(chg)); - chg.event_type = action; - chg.timestamp_ns = ktime_get_ns(); - gpio_desc_to_lineinfo(desc, &chg.info, false); - supinfo_to_lineinfo(desc, &chg.info); + ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC); + if (!ctx) { + pr_err("Failed to allocate memory for line info notification\n"); + return NOTIFY_DONE; + } - ret = kfifo_in_spinlocked(&cdev->events, &chg, 1, &cdev->wait.lock); - if (ret) - wake_up_poll(&cdev->wait, EPOLLIN); - else - pr_debug_ratelimited("lineinfo event FIFO is full - event dropped\n"); + ctx->chg.event_type = action; + ctx->chg.timestamp_ns = ktime_get_ns(); + gpio_desc_to_lineinfo(desc, &ctx->chg.info, true); + supinfo_to_lineinfo(desc, &ctx->chg.info); + /* Keep the GPIO device alive until we emit the event. */ + ctx->gdev = gpio_device_get(desc->gdev); + ctx->cdev = cdev; + /* Keep the file descriptor alive too. */ + get_file(ctx->cdev->fp); + + INIT_WORK(&ctx->work, lineinfo_changed_func); + queue_work(ctx->gdev->line_state_wq, &ctx->work); return NOTIFY_OK; } @@ -2803,6 +2850,7 @@ static int gpio_chrdev_open(struct inode *inode, struct file *file) goto out_unregister_line_notifier; 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Thu, 10 Oct 2024 02:10:39 -0700 (PDT) From: Bartosz Golaszewski Date: Thu, 10 Oct 2024 11:10:27 +0200 Subject: [PATCH v2 6/6] gpiolib: notify user-space about in-kernel line state changes Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241010-gpio-notify-in-kernel-events-v2-6-b560411f7c59@linaro.org> References: <20241010-gpio-notify-in-kernel-events-v2-0-b560411f7c59@linaro.org> In-Reply-To: <20241010-gpio-notify-in-kernel-events-v2-0-b560411f7c59@linaro.org> To: Linus Walleij , Bartosz Golaszewski , Kent Gibson Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Bartosz Golaszewski X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=7877; i=bartosz.golaszewski@linaro.org; h=from:subject:message-id; bh=emdseATUbYgPk+Xsat6ZPWRy+qomt58wS6OT5lF8raA=; b=owEBbQKS/ZANAwAKARGnLqAUcddyAcsmYgBnB5oHpr48emy3umBNf/nLJsFZqEjdB0aSjCUFf ePcCNg9q4KJAjMEAAEKAB0WIQQWnetsC8PEYBPSx58Rpy6gFHHXcgUCZweaBwAKCRARpy6gFHHX ckITD/oDPoKNQxYhDR9e0SHIrSjxle0eORVcn8MyYyedENcVWOVwInnhAb/zR1YxBRaVWZZuz0J gKsO36NSWe18hI0aMVmc/jG+JkLcyzHWOK5bZEqUqIfQPryjcCVaCICM6ytp6U2IJtACfXZN/D+ O308vDc++VVW4vlRop3sLa62Gzy7KR7vIsbAzXuf8ALtYqCmkKLDPyx73HGy+8aB4hZTEMTIXpJ z0/0mz6MIllXxhShm4H0xAUQg+wdsFCl+3z47WlihhlpR0aG6GgFjRv2kLlgMkxVx2HRBaJhbhI npeBtEY3Pu41PVXmOrxpwGWIRC4X0U3hVsQtesy274WugpPyRtv+V3SZz53/qbLbCVinLhfAswn eCnrkosLLnyFQ5WnJMO8BUEWwlHWZE6S38j0F/51n2pDKu3NzN2n4zT6SVKlEXCrj/25nC/knDv z5lpKYkG5kySSCkAhTBvL6l0qq2tmN5HJOPGVWmL2YtOMOezSLKiT0RCpxmy4C13Rz40abNLFq5 WAXEtdsTx33aEY6+FHskvnK788ix89Su3kNRFUfaUoPnubH7WCDUD+J22tGgEnBAllumv1Epw2g FV0GjjJcimaVdGR0ZBTzx2tHRdpdtyEc+TTn0tVrTrRUl67sN4/2EIJGYcB329KwK2bqu9uy/U3 iSzwIGfzk+unCGA== X-Developer-Key: i=bartosz.golaszewski@linaro.org; a=openpgp; fpr=169DEB6C0BC3C46013D2C79F11A72EA01471D772 From: Bartosz Golaszewski We currently only notify user-space about line config changes that are made from user-space. Any kernel config changes are not signalled. Let's improve the situation by emitting the events closer to the source. To that end let's call the relevant notifier chain from the functions setting direction, gpiod_set_config(), gpiod_set_consumer_name() and gpiod_toggle_active_low(). This covers all the options that we can inform the user-space about. We ignore events which don't have corresponding flags exported to user-space on purpose - otherwise the user would see a config-changed event but the associated line-info would remain unchanged. gpiod_direction_output/input() can be called from any context. Fortunately, we now emit line state events using an atomic notifier chain, so it's no longer an issue. Let's also add non-notifying wrappers around the direction setters in order to not emit superfluous reconfigure events when requesting the lines as the initial config should be part of the request notification. Signed-off-by: Bartosz Golaszewski --- drivers/gpio/gpiolib-cdev.c | 12 +++----- drivers/gpio/gpiolib.c | 71 ++++++++++++++++++++++++++++++++++++++++----- drivers/gpio/gpiolib.h | 2 ++ 3 files changed, 70 insertions(+), 15 deletions(-) diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index 7eae0b17a1d6..ff702fe59ecd 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -196,8 +196,6 @@ static long linehandle_set_config(struct linehandle_state *lh, if (ret) return ret; } - - gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); } return 0; } @@ -363,11 +361,11 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip) if (lflags & GPIOHANDLE_REQUEST_OUTPUT) { int val = !!handlereq.default_values[i]; - ret = gpiod_direction_output(desc, val); + ret = gpiod_direction_output_nonotify(desc, val); if (ret) goto out_free_lh; } else if (lflags & GPIOHANDLE_REQUEST_INPUT) { - ret = gpiod_direction_input(desc); + ret = gpiod_direction_input_nonotify(desc); if (ret) goto out_free_lh; } @@ -1568,8 +1566,6 @@ static long linereq_set_config(struct linereq *lr, void __user *ip) } WRITE_ONCE(line->edflags, edflags); - - gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); } return 0; } @@ -1826,11 +1822,11 @@ static int linereq_create(struct gpio_device *gdev, void __user *ip) if (flags & GPIO_V2_LINE_FLAG_OUTPUT) { int val = gpio_v2_line_config_output_value(lc, i); - ret = gpiod_direction_output(desc, val); + ret = gpiod_direction_output_nonotify(desc, val); if (ret) goto out_free_linereq; } else if (flags & GPIO_V2_LINE_FLAG_INPUT) { - ret = gpiod_direction_input(desc); + ret = gpiod_direction_input_nonotify(desc); if (ret) goto out_free_linereq; diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 9b10f47832d5..0986854ab1ed 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -2673,6 +2673,18 @@ int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce) * 0 on success, or negative errno on failure. */ int gpiod_direction_input(struct gpio_desc *desc) +{ + int ret; + + ret = gpiod_direction_input_nonotify(desc); + if (ret == 0) + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); + + return ret; +} +EXPORT_SYMBOL_GPL(gpiod_direction_input); + +int gpiod_direction_input_nonotify(struct gpio_desc *desc) { int ret = 0; @@ -2720,7 +2732,6 @@ int gpiod_direction_input(struct gpio_desc *desc) return ret; } -EXPORT_SYMBOL_GPL(gpiod_direction_input); static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value) { @@ -2782,8 +2793,15 @@ static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value) */ int gpiod_direction_output_raw(struct gpio_desc *desc, int value) { + int ret; + VALIDATE_DESC(desc); - return gpiod_direction_output_raw_commit(desc, value); + + ret = gpiod_direction_output_raw_commit(desc, value); + if (ret == 0) + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); + + return ret; } EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); @@ -2801,6 +2819,18 @@ EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); * 0 on success, or negative errno on failure. */ int gpiod_direction_output(struct gpio_desc *desc, int value) +{ + int ret; + + ret = gpiod_direction_output_nonotify(desc, value); + if (ret == 0) + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); + + return ret; +} +EXPORT_SYMBOL_GPL(gpiod_direction_output); + +int gpiod_direction_output_nonotify(struct gpio_desc *desc, int value) { unsigned long flags; int ret; @@ -2863,7 +2893,6 @@ int gpiod_direction_output(struct gpio_desc *desc, int value) set_bit(FLAG_IS_OUT, &desc->flags); return ret; } -EXPORT_SYMBOL_GPL(gpiod_direction_output); /** * gpiod_enable_hw_timestamp_ns - Enable hardware timestamp in nanoseconds. @@ -2942,13 +2971,34 @@ EXPORT_SYMBOL_GPL(gpiod_disable_hw_timestamp_ns); */ int gpiod_set_config(struct gpio_desc *desc, unsigned long config) { + int ret; + VALIDATE_DESC(desc); CLASS(gpio_chip_guard, guard)(desc); if (!guard.gc) return -ENODEV; - return gpio_do_set_config(guard.gc, gpio_chip_hwgpio(desc), config); + ret = gpio_do_set_config(guard.gc, gpio_chip_hwgpio(desc), config); + if (ret == 0) { + /* These are the only options we notify the userspace about. */ + switch (pinconf_to_config_param(config)) { + case PIN_CONFIG_BIAS_DISABLE: + case PIN_CONFIG_BIAS_PULL_DOWN: + case PIN_CONFIG_BIAS_PULL_UP: + case PIN_CONFIG_DRIVE_OPEN_DRAIN: + case PIN_CONFIG_DRIVE_OPEN_SOURCE: + case PIN_CONFIG_DRIVE_PUSH_PULL: + case PIN_CONFIG_INPUT_DEBOUNCE: + gpiod_line_state_notify(desc, + GPIO_V2_LINE_CHANGED_CONFIG); + break; + default: + break; + } + } + + return ret; } EXPORT_SYMBOL_GPL(gpiod_set_config); @@ -3015,6 +3065,7 @@ void gpiod_toggle_active_low(struct gpio_desc *desc) { VALIDATE_DESC_VOID(desc); change_bit(FLAG_ACTIVE_LOW, &desc->flags); + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); } EXPORT_SYMBOL_GPL(gpiod_toggle_active_low); @@ -3659,9 +3710,15 @@ EXPORT_SYMBOL_GPL(gpiod_cansleep); */ int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name) { + int ret; + VALIDATE_DESC(desc); - return desc_set_label(desc, name); + ret = desc_set_label(desc, name); + if (ret == 0) + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); + + return ret; } EXPORT_SYMBOL_GPL(gpiod_set_consumer_name); @@ -4539,10 +4596,10 @@ int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, /* Process flags */ if (dflags & GPIOD_FLAGS_BIT_DIR_OUT) - ret = gpiod_direction_output(desc, + ret = gpiod_direction_output_nonotify(desc, !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL)); else - ret = gpiod_direction_input(desc); + ret = gpiod_direction_input_nonotify(desc); return ret; } diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h index 2799157a1f6b..fc321d281346 100644 --- a/drivers/gpio/gpiolib.h +++ b/drivers/gpio/gpiolib.h @@ -155,6 +155,8 @@ int gpiod_set_array_value_complex(bool raw, bool can_sleep, int gpiod_set_transitory(struct gpio_desc *desc, bool transitory); void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action); +int gpiod_direction_output_nonotify(struct gpio_desc *desc, int value); +int gpiod_direction_input_nonotify(struct gpio_desc *desc); struct gpio_desc_label { struct rcu_head rh;