From 4e04b11800194f2ec756b5f3e9f2e559df5a0b1e Mon Sep 17 00:00:00 2001 From: Zheng Yongjun Date: Wed, 16 Dec 2020 21:16:53 +0800 Subject: [PATCH 1/5] leds: leds-lm3533: convert comma to semicolon Replace a comma between expression statements by a semicolon. Signed-off-by: Zheng Yongjun Signed-off-by: Pavel Machek --- drivers/leds/leds-lm3533.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/leds/leds-lm3533.c b/drivers/leds/leds-lm3533.c index b3edee703193..9dd205870525 100644 --- a/drivers/leds/leds-lm3533.c +++ b/drivers/leds/leds-lm3533.c @@ -679,7 +679,7 @@ static int lm3533_led_probe(struct platform_device *pdev) led->cdev.brightness_get = lm3533_led_get; led->cdev.blink_set = lm3533_led_blink_set; led->cdev.brightness = LED_OFF; - led->cdev.groups = lm3533_led_attribute_groups, + led->cdev.groups = lm3533_led_attribute_groups; led->id = pdev->id; mutex_init(&led->mutex); From 47854d2d2ba8f100c419557a7d9d8f155c0a1064 Mon Sep 17 00:00:00 2001 From: Zheng Yongjun Date: Mon, 14 Dec 2020 21:45:45 +0800 Subject: [PATCH 2/5] leds: leds-ariel: convert comma to semicolon Replace a comma between expression statements by a semicolon. Signed-off-by: Zheng Yongjun Reviewed-by: Alexander Dahl Signed-off-by: Pavel Machek --- drivers/leds/leds-ariel.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/leds/leds-ariel.c b/drivers/leds/leds-ariel.c index bb68ba23a7d4..49e1bddaa15e 100644 --- a/drivers/leds/leds-ariel.c +++ b/drivers/leds/leds-ariel.c @@ -96,14 +96,14 @@ static int ariel_led_probe(struct platform_device *pdev) return -ENOMEM; leds[0].ec_index = EC_BLUE_LED; - leds[0].led_cdev.name = "blue:power", + leds[0].led_cdev.name = "blue:power"; leds[0].led_cdev.default_trigger = "default-on"; leds[1].ec_index = EC_AMBER_LED; - leds[1].led_cdev.name = "amber:status", + leds[1].led_cdev.name = "amber:status"; leds[2].ec_index = EC_GREEN_LED; - leds[2].led_cdev.name = "green:status", + leds[2].led_cdev.name = "green:status"; leds[2].led_cdev.default_trigger = "default-on"; for (i = 0; i < NLEDS; i++) { From 27af8e2c90fba242460b01fa020e6e19ed68c495 Mon Sep 17 00:00:00 2001 From: Andrea Righi Date: Wed, 25 Nov 2020 16:18:22 +0100 Subject: [PATCH 3/5] leds: trigger: fix potential deadlock with libata We have the following potential deadlock condition: ======================================================== WARNING: possible irq lock inversion dependency detected 5.10.0-rc2+ #25 Not tainted -------------------------------------------------------- swapper/3/0 just changed the state of lock: ffff8880063bd618 (&host->lock){-...}-{2:2}, at: ata_bmdma_interrupt+0x27/0x200 but this lock took another, HARDIRQ-READ-unsafe lock in the past: (&trig->leddev_list_lock){.+.?}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&trig->leddev_list_lock); local_irq_disable(); lock(&host->lock); lock(&trig->leddev_list_lock); lock(&host->lock); *** DEADLOCK *** no locks held by swapper/3/0. the shortest dependencies between 2nd lock and 1st lock: -> (&trig->leddev_list_lock){.+.?}-{2:2} ops: 46 { HARDIRQ-ON-R at: lock_acquire+0x15f/0x420 _raw_read_lock+0x42/0x90 led_trigger_event+0x2b/0x70 rfkill_global_led_trigger_worker+0x94/0xb0 process_one_work+0x240/0x560 worker_thread+0x58/0x3d0 kthread+0x151/0x170 ret_from_fork+0x1f/0x30 IN-SOFTIRQ-R at: lock_acquire+0x15f/0x420 _raw_read_lock+0x42/0x90 led_trigger_event+0x2b/0x70 kbd_bh+0x9e/0xc0 tasklet_action_common.constprop.0+0xe9/0x100 tasklet_action+0x22/0x30 __do_softirq+0xcc/0x46d run_ksoftirqd+0x3f/0x70 smpboot_thread_fn+0x116/0x1f0 kthread+0x151/0x170 ret_from_fork+0x1f/0x30 SOFTIRQ-ON-R at: lock_acquire+0x15f/0x420 _raw_read_lock+0x42/0x90 led_trigger_event+0x2b/0x70 rfkill_global_led_trigger_worker+0x94/0xb0 process_one_work+0x240/0x560 worker_thread+0x58/0x3d0 kthread+0x151/0x170 ret_from_fork+0x1f/0x30 INITIAL READ USE at: lock_acquire+0x15f/0x420 _raw_read_lock+0x42/0x90 led_trigger_event+0x2b/0x70 rfkill_global_led_trigger_worker+0x94/0xb0 process_one_work+0x240/0x560 worker_thread+0x58/0x3d0 kthread+0x151/0x170 ret_from_fork+0x1f/0x30 } ... key at: [] __key.0+0x0/0x10 ... acquired at: _raw_read_lock+0x42/0x90 led_trigger_blink_oneshot+0x3b/0x90 ledtrig_disk_activity+0x3c/0xa0 ata_qc_complete+0x26/0x450 ata_do_link_abort+0xa3/0xe0 ata_port_freeze+0x2e/0x40 ata_hsm_qc_complete+0x94/0xa0 ata_sff_hsm_move+0x177/0x7a0 ata_sff_pio_task+0xc7/0x1b0 process_one_work+0x240/0x560 worker_thread+0x58/0x3d0 kthread+0x151/0x170 ret_from_fork+0x1f/0x30 -> (&host->lock){-...}-{2:2} ops: 69 { IN-HARDIRQ-W at: lock_acquire+0x15f/0x420 _raw_spin_lock_irqsave+0x52/0xa0 ata_bmdma_interrupt+0x27/0x200 __handle_irq_event_percpu+0xd5/0x2b0 handle_irq_event+0x57/0xb0 handle_edge_irq+0x8c/0x230 asm_call_irq_on_stack+0xf/0x20 common_interrupt+0x100/0x1c0 asm_common_interrupt+0x1e/0x40 native_safe_halt+0xe/0x10 arch_cpu_idle+0x15/0x20 default_idle_call+0x59/0x1c0 do_idle+0x22c/0x2c0 cpu_startup_entry+0x20/0x30 start_secondary+0x11d/0x150 secondary_startup_64_no_verify+0xa6/0xab INITIAL USE at: lock_acquire+0x15f/0x420 _raw_spin_lock_irqsave+0x52/0xa0 ata_dev_init+0x54/0xe0 ata_link_init+0x8b/0xd0 ata_port_alloc+0x1f1/0x210 ata_host_alloc+0xf1/0x130 ata_host_alloc_pinfo+0x14/0xb0 ata_pci_sff_prepare_host+0x41/0xa0 ata_pci_bmdma_prepare_host+0x14/0x30 piix_init_one+0x21f/0x600 local_pci_probe+0x48/0x80 pci_device_probe+0x105/0x1c0 really_probe+0x221/0x490 driver_probe_device+0xe9/0x160 device_driver_attach+0xb2/0xc0 __driver_attach+0x91/0x150 bus_for_each_dev+0x81/0xc0 driver_attach+0x1e/0x20 bus_add_driver+0x138/0x1f0 driver_register+0x91/0xf0 __pci_register_driver+0x73/0x80 piix_init+0x1e/0x2e do_one_initcall+0x5f/0x2d0 kernel_init_freeable+0x26f/0x2cf kernel_init+0xe/0x113 ret_from_fork+0x1f/0x30 } ... key at: [] __key.6+0x0/0x10 ... acquired at: __lock_acquire+0x9da/0x2370 lock_acquire+0x15f/0x420 _raw_spin_lock_irqsave+0x52/0xa0 ata_bmdma_interrupt+0x27/0x200 __handle_irq_event_percpu+0xd5/0x2b0 handle_irq_event+0x57/0xb0 handle_edge_irq+0x8c/0x230 asm_call_irq_on_stack+0xf/0x20 common_interrupt+0x100/0x1c0 asm_common_interrupt+0x1e/0x40 native_safe_halt+0xe/0x10 arch_cpu_idle+0x15/0x20 default_idle_call+0x59/0x1c0 do_idle+0x22c/0x2c0 cpu_startup_entry+0x20/0x30 start_secondary+0x11d/0x150 secondary_startup_64_no_verify+0xa6/0xab This lockdep splat is reported after: commit e918188611f0 ("locking: More accurate annotations for read_lock()") To clarify: - read-locks are recursive only in interrupt context (when in_interrupt() returns true) - after acquiring host->lock in CPU1, another cpu (i.e. CPU2) may call write_lock(&trig->leddev_list_lock) that would be blocked by CPU0 that holds trig->leddev_list_lock in read-mode - when CPU1 (ata_ac_complete()) tries to read-lock trig->leddev_list_lock, it would be blocked by the write-lock waiter on CPU2 (because we are not in interrupt context, so the read-lock is not recursive) - at this point if an interrupt happens on CPU0 and ata_bmdma_interrupt() is executed it will try to acquire host->lock, that is held by CPU1, that is currently blocked by CPU2, so: * CPU0 blocked by CPU1 * CPU1 blocked by CPU2 * CPU2 blocked by CPU0 *** DEADLOCK *** The deadlock scenario is better represented by the following schema (thanks to Boqun Feng for the schema and the detailed explanation of the deadlock condition): CPU 0: CPU 1: CPU 2: ----- ----- ----- led_trigger_event(): read_lock(&trig->leddev_list_lock); ata_hsm_qc_complete(): spin_lock_irqsave(&host->lock); write_lock(&trig->leddev_list_lock); ata_port_freeze(): ata_do_link_abort(): ata_qc_complete(): ledtrig_disk_activity(): led_trigger_blink_oneshot(): read_lock(&trig->leddev_list_lock); // ^ not in in_interrupt() context, so could get blocked by CPU 2 ata_bmdma_interrupt(): spin_lock_irqsave(&host->lock); Fix by using read_lock_irqsave/irqrestore() in led_trigger_event(), so that no interrupt can happen in between, preventing the deadlock condition. Apply the same change to led_trigger_blink_setup() as well, since the same deadlock scenario can also happen in power_supply_update_bat_leds() -> led_trigger_blink() -> led_trigger_blink_setup() (workqueue context), and potentially prevent other similar usages. Link: https://lore.kernel.org/lkml/20201101092614.GB3989@xps-13-7390/ Fixes: eb25cb9956cc ("leds: convert IDE trigger to common disk trigger") Signed-off-by: Andrea Righi Signed-off-by: Pavel Machek --- drivers/leds/led-triggers.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c index 91da90cfb11d..4e7b78a84149 100644 --- a/drivers/leds/led-triggers.c +++ b/drivers/leds/led-triggers.c @@ -378,14 +378,15 @@ void led_trigger_event(struct led_trigger *trig, enum led_brightness brightness) { struct led_classdev *led_cdev; + unsigned long flags; if (!trig) return; - read_lock(&trig->leddev_list_lock); + read_lock_irqsave(&trig->leddev_list_lock, flags); list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list) led_set_brightness(led_cdev, brightness); - read_unlock(&trig->leddev_list_lock); + read_unlock_irqrestore(&trig->leddev_list_lock, flags); } EXPORT_SYMBOL_GPL(led_trigger_event); @@ -396,11 +397,12 @@ static void led_trigger_blink_setup(struct led_trigger *trig, int invert) { struct led_classdev *led_cdev; + unsigned long flags; if (!trig) return; - read_lock(&trig->leddev_list_lock); + read_lock_irqsave(&trig->leddev_list_lock, flags); list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list) { if (oneshot) led_blink_set_oneshot(led_cdev, delay_on, delay_off, @@ -408,7 +410,7 @@ static void led_trigger_blink_setup(struct led_trigger *trig, else led_blink_set(led_cdev, delay_on, delay_off); } - read_unlock(&trig->leddev_list_lock); + read_unlock_irqrestore(&trig->leddev_list_lock, flags); } void led_trigger_blink(struct led_trigger *trig, From c8283eb79d879ef898f4224ba30e554f83904b0a Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Sun, 3 Jan 2021 00:15:09 +0100 Subject: [PATCH 4/5] dt-bindings: leds: Add DT binding for Richtek RT8515 Add a YAML devicetree binding for the Richtek RT8515 dual channel flash/torch LED driver. Cc: Sakari Ailus Cc: newbytee@protonmail.com Cc: Stephan Gerhold Cc: phone-devel@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: devicetree@vger.kernel.org Reviewed-by: Rob Herring Reviewed-by: Sakari Ailus Signed-off-by: Linus Walleij Signed-off-by: Pavel Machek --- .../bindings/leds/richtek,rt8515.yaml | 111 ++++++++++++++++++ 1 file changed, 111 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/richtek,rt8515.yaml diff --git a/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml b/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml new file mode 100644 index 000000000000..68c328eec03b --- /dev/null +++ b/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml @@ -0,0 +1,111 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/leds/richtek,rt8515.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Richtek RT8515 1.5A dual channel LED driver + +maintainers: + - Linus Walleij + +description: | + The Richtek RT8515 is a dual channel (two mode) LED driver that + supports driving a white LED in flash or torch mode. The maximum + current for each mode is defined in hardware using two resistors + RFS and RTS. + +properties: + compatible: + const: richtek,rt8515 + + enf-gpios: + maxItems: 1 + description: A connection to the 'ENF' (enable flash) pin. + + ent-gpios: + maxItems: 1 + description: A connection to the 'ENT' (enable torch) pin. + + richtek,rfs-ohms: + minimum: 7680 + maximum: 367000 + description: The resistance value of the RFS resistor. This + resistors limits the maximum flash current. This must be set + for the property flash-max-microamp to work, the RFS resistor + defines the range of the dimmer setting (brightness) of the + flash LED. + + richtek,rts-ohms: + minimum: 7680 + maximum: 367000 + description: The resistance value of the RTS resistor. This + resistors limits the maximum torch current. This must be set + for the property torch-max-microamp to work, the RTS resistor + defines the range of the dimmer setting (brightness) of the + torch LED. + + led: + type: object + $ref: common.yaml# + properties: + function: true + color: true + flash-max-timeout-us: true + + flash-max-microamp: + maximum: 700000 + description: The maximum current for flash mode + is hardwired to the component using the RFS resistor to + ground. The maximum hardware current setting is calculated + according to the formula Imax = 5500 / RFS. The lowest + allowed resistance value is 7.86 kOhm giving an absolute + maximum current of 700mA. By setting this attribute in + the device tree, you can further restrict the maximum + current below the hardware limit. This requires the RFS + to be defined as it defines the maximum range. + + led-max-microamp: + maximum: 700000 + description: The maximum current for torch mode + is hardwired to the component using the RTS resistor to + ground. The maximum hardware current setting is calculated + according to the formula Imax = 5500 / RTS. The lowest + allowed resistance value is 7.86 kOhm giving an absolute + maximum current of 700mA. By setting this attribute in + the device tree, you can further restrict the maximum + current below the hardware limit. This requires the RTS + to be defined as it defines the maximum range. + + additionalProperties: false + +required: + - compatible + - ent-gpios + - enf-gpios + - led + +additionalProperties: false + +examples: + - | + #include + #include + + led-controller { + compatible = "richtek,rt8515"; + enf-gpios = <&gpio4 12 GPIO_ACTIVE_HIGH>; + ent-gpios = <&gpio4 13 GPIO_ACTIVE_HIGH>; + richtek,rfs-ohms = <16000>; + richtek,rts-ohms = <100000>; + + led { + function = LED_FUNCTION_FLASH; + color = ; + flash-max-timeout-us = <250000>; + flash-max-microamp = <150000>; + led-max-microamp = <25000>; + }; + }; + +... From e1c6edcbea13de025c3406645b4cce4ac3baf973 Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Sun, 3 Jan 2021 00:15:10 +0100 Subject: [PATCH 5/5] leds: rt8515: Add Richtek RT8515 LED driver This adds a driver for the Richtek RT8515 dual channel torch/flash white LED driver. This LED driver is found in some mobile phones from Samsung such as the GT-S7710 and GT-I8190. A V4L interface is added. We do not have a proper datasheet for the RT8515 but it turns out that RT9387A has a public datasheet and is essentially the same chip. We designed the driver in accordance with this datasheet. The day someone needs to drive a RT9387A this driver can probably easily be augmented to handle that chip too. Sakari Ailus, Pavel Machek and Andy Shevchenko helped significantly in getting this driver right. Cc: Sakari Ailus Cc: newbytee@protonmail.com Cc: Stephan Gerhold Cc: linux-media@vger.kernel.org Cc: phone-devel@vger.kernel.org Reviewed-by: Sakari Ailus Signed-off-by: Linus Walleij Signed-off-by: Pavel Machek --- drivers/leds/Kconfig | 3 + drivers/leds/Makefile | 3 + drivers/leds/flash/Kconfig | 15 ++ drivers/leds/flash/Makefile | 3 + drivers/leds/flash/leds-rt8515.c | 397 +++++++++++++++++++++++++++++++ 5 files changed, 421 insertions(+) create mode 100644 drivers/leds/flash/Kconfig create mode 100644 drivers/leds/flash/Makefile create mode 100644 drivers/leds/flash/leds-rt8515.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 849d3c5f908e..6c1d8b69a465 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -928,6 +928,9 @@ config LEDS_ACER_A500 This option enables support for the Power Button LED of Acer Iconia Tab A500. +comment "Flash and Torch LED drivers" +source "drivers/leds/flash/Kconfig" + comment "LED Triggers" source "drivers/leds/trigger/Kconfig" diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 73e603e1727e..156c0b4e60d9 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -103,5 +103,8 @@ obj-$(CONFIG_LEDS_SPI_BYTE) += leds-spi-byte.o # LED Userspace Drivers obj-$(CONFIG_LEDS_USER) += uleds.o +# Flash and Torch LED Drivers +obj-$(CONFIG_LEDS_CLASS_FLASH) += flash/ + # LED Triggers obj-$(CONFIG_LEDS_TRIGGERS) += trigger/ diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig new file mode 100644 index 000000000000..d21d273ef3da --- /dev/null +++ b/drivers/leds/flash/Kconfig @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 + +if LEDS_CLASS_FLASH + +config LEDS_RT8515 + tristate "LED support for Richtek RT8515 flash/torch LED" + depends on GPIOLIB + help + This option enables support for the Richtek RT8515 flash + and torch LEDs found on some mobile phones. + + To compile this driver as a module, choose M here: the module + will be called leds-rt8515. + +endif # LEDS_CLASS_FLASH diff --git a/drivers/leds/flash/Makefile b/drivers/leds/flash/Makefile new file mode 100644 index 000000000000..e990e257f4d7 --- /dev/null +++ b/drivers/leds/flash/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_LEDS_RT8515) += leds-rt8515.o diff --git a/drivers/leds/flash/leds-rt8515.c b/drivers/leds/flash/leds-rt8515.c new file mode 100644 index 000000000000..590bfa180d10 --- /dev/null +++ b/drivers/leds/flash/leds-rt8515.c @@ -0,0 +1,397 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * LED driver for Richtek RT8515 flash/torch white LEDs + * found on some Samsung mobile phones. + * + * This is a 1.5A Boost dual channel driver produced around 2011. + * + * The component lacks a datasheet, but in the schematic picture + * from the LG P970 service manual you can see the connections + * from the RT8515 to the LED, with two resistors connected + * from the pins "RFS" and "RTS" to ground. + * + * On the LG P970: + * RFS (resistance flash setting?) is 20 kOhm + * RTS (resistance torch setting?) is 39 kOhm + * + * Some sleuthing finds us the RT9387A which we have a datasheet for: + * https://static5.arrow.com/pdfs/2014/7/27/8/21/12/794/rtt_/manual/94download_ds.jspprt9387a.jspprt9387a.pdf + * This apparently works the same way so in theory this driver + * should cover RT9387A as well. This has not been tested, please + * update the compatibles if you add RT9387A support. + * + * Linus Walleij + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +/* We can provide 15-700 mA out to the LED */ +#define RT8515_MIN_IOUT_MA 15 +#define RT8515_MAX_IOUT_MA 700 +/* The maximum intensity is 1-16 for flash and 1-100 for torch */ +#define RT8515_FLASH_MAX 16 +#define RT8515_TORCH_MAX 100 + +#define RT8515_TIMEOUT_US 250000U +#define RT8515_MAX_TIMEOUT_US 300000U + +struct rt8515 { + struct led_classdev_flash fled; + struct device *dev; + struct v4l2_flash *v4l2_flash; + struct mutex lock; + struct regulator *reg; + struct gpio_desc *enable_torch; + struct gpio_desc *enable_flash; + struct timer_list powerdown_timer; + u32 max_timeout; /* Flash max timeout */ + int flash_max_intensity; + int torch_max_intensity; +}; + +static struct rt8515 *to_rt8515(struct led_classdev_flash *fled) +{ + return container_of(fled, struct rt8515, fled); +} + +static void rt8515_gpio_led_off(struct rt8515 *rt) +{ + gpiod_set_value(rt->enable_flash, 0); + gpiod_set_value(rt->enable_torch, 0); +} + +static void rt8515_gpio_brightness_commit(struct gpio_desc *gpiod, + int brightness) +{ + int i; + + /* + * Toggling a GPIO line with a small delay increases the + * brightness one step at a time. + */ + for (i = 0; i < brightness; i++) { + gpiod_set_value(gpiod, 0); + udelay(1); + gpiod_set_value(gpiod, 1); + udelay(1); + } +} + +/* This is setting the torch light level */ +static int rt8515_led_brightness_set(struct led_classdev *led, + enum led_brightness brightness) +{ + struct led_classdev_flash *fled = lcdev_to_flcdev(led); + struct rt8515 *rt = to_rt8515(fled); + + mutex_lock(&rt->lock); + + if (brightness == LED_OFF) { + /* Off */ + rt8515_gpio_led_off(rt); + } else if (brightness < RT8515_TORCH_MAX) { + /* Step it up to movie mode brightness using the flash pin */ + rt8515_gpio_brightness_commit(rt->enable_torch, brightness); + } else { + /* Max torch brightness requested */ + gpiod_set_value(rt->enable_torch, 1); + } + + mutex_unlock(&rt->lock); + + return 0; +} + +static int rt8515_led_flash_strobe_set(struct led_classdev_flash *fled, + bool state) +{ + struct rt8515 *rt = to_rt8515(fled); + struct led_flash_setting *timeout = &fled->timeout; + int brightness = rt->flash_max_intensity; + + mutex_lock(&rt->lock); + + if (state) { + /* Enable LED flash mode and set brightness */ + rt8515_gpio_brightness_commit(rt->enable_flash, brightness); + /* Set timeout */ + mod_timer(&rt->powerdown_timer, + jiffies + usecs_to_jiffies(timeout->val)); + } else { + del_timer_sync(&rt->powerdown_timer); + /* Turn the LED off */ + rt8515_gpio_led_off(rt); + } + + fled->led_cdev.brightness = LED_OFF; + /* After this the torch LED will be disabled */ + + mutex_unlock(&rt->lock); + + return 0; +} + +static int rt8515_led_flash_strobe_get(struct led_classdev_flash *fled, + bool *state) +{ + struct rt8515 *rt = to_rt8515(fled); + + *state = timer_pending(&rt->powerdown_timer); + + return 0; +} + +static int rt8515_led_flash_timeout_set(struct led_classdev_flash *fled, + u32 timeout) +{ + /* The timeout is stored in the led-class-flash core */ + return 0; +} + +static const struct led_flash_ops rt8515_flash_ops = { + .strobe_set = rt8515_led_flash_strobe_set, + .strobe_get = rt8515_led_flash_strobe_get, + .timeout_set = rt8515_led_flash_timeout_set, +}; + +static void rt8515_powerdown_timer(struct timer_list *t) +{ + struct rt8515 *rt = from_timer(rt, t, powerdown_timer); + + /* Turn the LED off */ + rt8515_gpio_led_off(rt); +} + +static void rt8515_init_flash_timeout(struct rt8515 *rt) +{ + struct led_classdev_flash *fled = &rt->fled; + struct led_flash_setting *s; + + /* Init flash timeout setting */ + s = &fled->timeout; + s->min = 1; + s->max = rt->max_timeout; + s->step = 1; + /* + * Set default timeout to RT8515_TIMEOUT_US except if + * max_timeout from DT is lower. + */ + s->val = min(rt->max_timeout, RT8515_TIMEOUT_US); +} + +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS) +/* Configure the V2L2 flash subdevice */ +static void rt8515_init_v4l2_flash_config(struct rt8515 *rt, + struct v4l2_flash_config *v4l2_sd_cfg) +{ + struct led_classdev *led = &rt->fled.led_cdev; + struct led_flash_setting *s; + + strscpy(v4l2_sd_cfg->dev_name, led->dev->kobj.name, + sizeof(v4l2_sd_cfg->dev_name)); + + /* + * Init flash intensity setting: this is a linear scale + * capped from the device tree max intensity setting + * 1..flash_max_intensity + */ + s = &v4l2_sd_cfg->intensity; + s->min = 1; + s->max = rt->flash_max_intensity; + s->step = 1; + s->val = s->max; +} + +static void rt8515_v4l2_flash_release(struct rt8515 *rt) +{ + v4l2_flash_release(rt->v4l2_flash); +} + +#else +static void rt8515_init_v4l2_flash_config(struct rt8515 *rt, + struct v4l2_flash_config *v4l2_sd_cfg) +{ +} + +static void rt8515_v4l2_flash_release(struct rt8515 *rt) +{ +} +#endif + +static void rt8515_determine_max_intensity(struct rt8515 *rt, + struct fwnode_handle *led, + const char *resistance, + const char *max_ua_prop, int hw_max, + int *max_intensity_setting) +{ + u32 res = 0; /* Can't be 0 so 0 is undefined */ + u32 ua; + u32 max_ma; + int max_intensity; + int ret; + + fwnode_property_read_u32(rt->dev->fwnode, resistance, &res); + ret = fwnode_property_read_u32(led, max_ua_prop, &ua); + + /* Missing info in DT, OK go with hardware maxima */ + if (ret || res == 0) { + dev_err(rt->dev, + "either %s or %s missing from DT, using HW max\n", + resistance, max_ua_prop); + max_ma = RT8515_MAX_IOUT_MA; + max_intensity = hw_max; + goto out_assign_max; + } + + /* + * Formula from the datasheet, this is the maximum current + * defined by the hardware. + */ + max_ma = (5500 * 1000) / res; + /* + * Calculate max intensity (linear scaling) + * Formula is ((ua / 1000) / max_ma) * 100, then simplified + */ + max_intensity = (ua / 10) / max_ma; + + dev_info(rt->dev, + "current restricted from %u to %u mA, max intensity %d/100\n", + max_ma, (ua / 1000), max_intensity); + +out_assign_max: + dev_info(rt->dev, "max intensity %d/%d = %d mA\n", + max_intensity, hw_max, max_ma); + *max_intensity_setting = max_intensity; +} + +static int rt8515_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct fwnode_handle *child; + struct rt8515 *rt; + struct led_classdev *led; + struct led_classdev_flash *fled; + struct led_init_data init_data = {}; + struct v4l2_flash_config v4l2_sd_cfg = {}; + int ret; + + rt = devm_kzalloc(dev, sizeof(*rt), GFP_KERNEL); + if (!rt) + return -ENOMEM; + + rt->dev = dev; + fled = &rt->fled; + led = &fled->led_cdev; + + /* ENF - Enable Flash line */ + rt->enable_flash = devm_gpiod_get(dev, "enf", GPIOD_OUT_LOW); + if (IS_ERR(rt->enable_flash)) + return dev_err_probe(dev, PTR_ERR(rt->enable_flash), + "cannot get ENF (enable flash) GPIO\n"); + + /* ENT - Enable Torch line */ + rt->enable_torch = devm_gpiod_get(dev, "ent", GPIOD_OUT_LOW); + if (IS_ERR(rt->enable_torch)) + return dev_err_probe(dev, PTR_ERR(rt->enable_torch), + "cannot get ENT (enable torch) GPIO\n"); + + child = fwnode_get_next_available_child_node(dev->fwnode, NULL); + if (!child) { + dev_err(dev, + "No fwnode child node found for connected LED.\n"); + return -EINVAL; + } + init_data.fwnode = child; + + rt8515_determine_max_intensity(rt, child, "richtek,rfs-ohms", + "flash-max-microamp", + RT8515_FLASH_MAX, + &rt->flash_max_intensity); + rt8515_determine_max_intensity(rt, child, "richtek,rts-ohms", + "led-max-microamp", + RT8515_TORCH_MAX, + &rt->torch_max_intensity); + + ret = fwnode_property_read_u32(child, "flash-max-timeout-us", + &rt->max_timeout); + if (ret) { + rt->max_timeout = RT8515_MAX_TIMEOUT_US; + dev_warn(dev, + "flash-max-timeout-us property missing\n"); + } + timer_setup(&rt->powerdown_timer, rt8515_powerdown_timer, 0); + rt8515_init_flash_timeout(rt); + + fled->ops = &rt8515_flash_ops; + + led->max_brightness = rt->torch_max_intensity; + led->brightness_set_blocking = rt8515_led_brightness_set; + led->flags |= LED_CORE_SUSPENDRESUME | LED_DEV_CAP_FLASH; + + mutex_init(&rt->lock); + + platform_set_drvdata(pdev, rt); + + ret = devm_led_classdev_flash_register_ext(dev, fled, &init_data); + if (ret) { + dev_err(dev, "can't register LED %s\n", led->name); + mutex_destroy(&rt->lock); + return ret; + } + + rt8515_init_v4l2_flash_config(rt, &v4l2_sd_cfg); + + /* Create a V4L2 Flash device if V4L2 flash is enabled */ + rt->v4l2_flash = v4l2_flash_init(dev, child, fled, NULL, &v4l2_sd_cfg); + if (IS_ERR(rt->v4l2_flash)) { + ret = PTR_ERR(rt->v4l2_flash); + dev_err(dev, "failed to register V4L2 flash device (%d)\n", + ret); + /* + * Continue without the V4L2 flash + * (we still have the classdev) + */ + } + + return 0; +} + +static int rt8515_remove(struct platform_device *pdev) +{ + struct rt8515 *rt = platform_get_drvdata(pdev); + + rt8515_v4l2_flash_release(rt); + del_timer_sync(&rt->powerdown_timer); + mutex_destroy(&rt->lock); + + return 0; +} + +static const struct of_device_id rt8515_match[] = { + { .compatible = "richtek,rt8515", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rt8515_match); + +static struct platform_driver rt8515_driver = { + .driver = { + .name = "rt8515", + .of_match_table = rt8515_match, + }, + .probe = rt8515_probe, + .remove = rt8515_remove, +}; +module_platform_driver(rt8515_driver); + +MODULE_AUTHOR("Linus Walleij "); +MODULE_DESCRIPTION("Richtek RT8515 LED driver"); +MODULE_LICENSE("GPL");