diff options
Diffstat (limited to 'drivers/leds/leds-tca6507.c')
| -rw-r--r-- | drivers/leds/leds-tca6507.c | 333 |
1 files changed, 148 insertions, 185 deletions
diff --git a/drivers/leds/leds-tca6507.c b/drivers/leds/leds-tca6507.c index 98fe021ba276..fd0e8bab9a4b 100644 --- a/drivers/leds/leds-tca6507.c +++ b/drivers/leds/leds-tca6507.c @@ -1,80 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * leds-tca6507 * * The TCA6507 is a programmable LED controller that can drive 7 * separate lines either by holding them low, or by pulsing them * with modulated width. - * The modulation can be varied in a simple pattern to produce a blink or - * double-blink. + * The modulation can be varied in a simple pattern to produce a + * blink or double-blink. * - * This driver can configure each line either as a 'GPIO' which is out-only - * (no pull-up) or as an LED with variable brightness and hardware-assisted - * blinking. + * This driver can configure each line either as a 'GPIO' which is + * out-only (pull-up resistor required) or as an LED with variable + * brightness and hardware-assisted blinking. * - * Apart from OFF and ON there are three programmable brightness levels which - * can be programmed from 0 to 15 and indicate how many 500usec intervals in - * each 8msec that the led is 'on'. The levels are named MASTER, BANK0 and - * BANK1. + * Apart from OFF and ON there are three programmable brightness + * levels which can be programmed from 0 to 15 and indicate how many + * 500usec intervals in each 8msec that the led is 'on'. The levels + * are named MASTER, BANK0 and BANK1. * - * There are two different blink rates that can be programmed, each with - * separate time for rise, on, fall, off and second-off. Thus if 3 or more - * different non-trivial rates are required, software must be used for the extra - * rates. The two different blink rates must align with the two levels BANK0 and - * BANK1. - * This driver does not support double-blink so 'second-off' always matches - * 'off'. + * There are two different blink rates that can be programmed, each + * with separate time for rise, on, fall, off and second-off. Thus if + * 3 or more different non-trivial rates are required, software must + * be used for the extra rates. The two different blink rates must + * align with the two levels BANK0 and BANK1. This driver does not + * support double-blink so 'second-off' always matches 'off'. * - * Only 16 different times can be programmed in a roughly logarithmic scale from - * 64ms to 16320ms. To be precise the possible times are: + * Only 16 different times can be programmed in a roughly logarithmic + * scale from 64ms to 16320ms. To be precise the possible times are: * 0, 64, 128, 192, 256, 384, 512, 768, * 1024, 1536, 2048, 3072, 4096, 5760, 8128, 16320 * - * Times that cannot be closely matched with these must be - * handled in software. This driver allows 12.5% error in matching. + * Times that cannot be closely matched with these must be handled in + * software. This driver allows 12.5% error in matching. * - * This driver does not allow rise/fall rates to be set explicitly. When trying - * to match a given 'on' or 'off' period, an appropriate pair of 'change' and - * 'hold' times are chosen to get a close match. If the target delay is even, - * the 'change' number will be the smaller; if odd, the 'hold' number will be - * the smaller. - - * Choosing pairs of delays with 12.5% errors allows us to match delays in the - * ranges: 56-72, 112-144, 168-216, 224-27504, 28560-36720. - * 26% of the achievable sums can be matched by multiple pairings. For example - * 1536 == 1536+0, 1024+512, or 768+768. This driver will always choose the - * pairing with the least maximum - 768+768 in this case. Other pairings are - * not available. + * This driver does not allow rise/fall rates to be set explicitly. + * When trying to match a given 'on' or 'off' period, an appropriate + * pair of 'change' and 'hold' times are chosen to get a close match. + * If the target delay is even, the 'change' number will be the + * smaller; if odd, the 'hold' number will be the smaller. + + * Choosing pairs of delays with 12.5% errors allows us to match + * delays in the ranges: 56-72, 112-144, 168-216, 224-27504, + * 28560-36720. + * 26% of the achievable sums can be matched by multiple pairings. + * For example 1536 == 1536+0, 1024+512, or 768+768. + * This driver will always choose the pairing with the least + * maximum - 768+768 in this case. Other pairings are not available. * - * Access to the 3 levels and 2 blinks are on a first-come, first-served basis. - * Access can be shared by multiple leds if they have the same level and - * either same blink rates, or some don't blink. - * When a led changes, it relinquishes access and tries again, so it might - * lose access to hardware blink. - * If a blink engine cannot be allocated, software blink is used. - * If the desired brightness cannot be allocated, the closest available non-zero - * brightness is used. As 'full' is always available, the worst case would be - * to have two different blink rates at '1', with Max at '2', then other leds - * will have to choose between '2' and '16'. Hopefully this is not likely. + * Access to the 3 levels and 2 blinks are on a first-come, + * first-served basis. Access can be shared by multiple leds if they + * have the same level and either same blink rates, or some don't + * blink. When a led changes, it relinquishes access and tries again, + * so it might lose access to hardware blink. * - * Each bank (BANK0 and BANK1) has two usage counts - LEDs using the brightness - * and LEDs using the blink. It can only be reprogrammed when the appropriate - * counter is zero. The MASTER level has a single usage count. + * If a blink engine cannot be allocated, software blink is used. If + * the desired brightness cannot be allocated, the closest available + * non-zero brightness is used. As 'full' is always available, the + * worst case would be to have two different blink rates at '1', with + * Max at '2', then other leds will have to choose between '2' and + * '16'. Hopefully this is not likely. * - * Each Led has programmable 'on' and 'off' time as milliseconds. With each - * there is a flag saying if it was explicitly requested or defaulted. - * Similarly the banks know if each time was explicit or a default. Defaults - * are permitted to be changed freely - they are not recognised when matching. - * - * - * An led-tca6507 device must be provided with platform data. This data - * lists for each output: the name, default trigger, and whether the signal - * is being used as a GPiO rather than an led. 'struct led_plaform_data' - * is used for this. If 'name' is NULL, the output isn't used. If 'flags' - * is TCA6507_MAKE_CPIO, the output is a GPO. - * The "struct led_platform_data" can be embedded in a - * "struct tca6507_platform_data" which adds a 'gpio_base' for the GPiOs, - * and a 'setup' callback which is called once the GPiOs are available. + * Each bank (BANK0 and BANK1) has two usage counts - LEDs using the + * brightness and LEDs using the blink. It can only be reprogrammed + * when the appropriate counter is zero. The MASTER level has a + * single usage count. * + * Each LED has programmable 'on' and 'off' time as milliseconds. + * With each there is a flag saying if it was explicitly requested or + * defaulted. Similarly the banks know if each time was explicit or a + * default. Defaults are permitted to be changed freely - they are + * not recognised when matching. */ #include <linux/module.h> @@ -82,10 +76,9 @@ #include <linux/leds.h> #include <linux/err.h> #include <linux/i2c.h> -#include <linux/gpio.h> +#include <linux/gpio/driver.h> +#include <linux/property.h> #include <linux/workqueue.h> -#include <linux/leds-tca6507.h> -#include <linux/of.h> /* LED select registers determine the source that drives LED outputs */ #define TCA6507_LS_LED_OFF 0x0 /* Output HI-Z (off) */ @@ -97,6 +90,12 @@ #define TCA6507_LS_BLINK0 0x6 /* Blink at Bank0 rate */ #define TCA6507_LS_BLINK1 0x7 /* Blink at Bank1 rate */ +struct tca6507_platform_data { + struct led_platform_data leds; +}; + +#define TCA6507_MAKE_GPIO 1 + enum { BANK0, BANK1, @@ -178,7 +177,6 @@ struct tca6507_chip { } leds[NUM_LEDS]; #ifdef CONFIG_GPIOLIB struct gpio_chip gpio; - const char *gpio_name[NUM_LEDS]; int gpio_map[NUM_LEDS]; #endif }; @@ -192,17 +190,18 @@ MODULE_DEVICE_TABLE(i2c, tca6507_id); static int choose_times(int msec, int *c1p, int *c2p) { /* - * Choose two timecodes which add to 'msec' as near as possible. - * The first returned is the 'on' or 'off' time. The second is to be - * used as a 'fade-on' or 'fade-off' time. If 'msec' is even, - * the first will not be smaller than the second. If 'msec' is odd, - * the first will not be larger than the second. - * If we cannot get a sum within 1/8 of 'msec' fail with -EINVAL, - * otherwise return the sum that was achieved, plus 1 if the first is - * smaller. - * If two possibilities are equally good (e.g. 512+0, 256+256), choose - * the first pair so there is more change-time visible (i.e. it is - * softer). + * Choose two timecodes which add to 'msec' as near as + * possible. The first returned is the 'on' or 'off' time. + * The second is to be used as a 'fade-on' or 'fade-off' time. + * If 'msec' is even, the first will not be smaller than the + * second. If 'msec' is odd, the first will not be larger + * than the second. + * If we cannot get a sum within 1/8 of 'msec' fail with + * -EINVAL, otherwise return the sum that was achieved, plus 1 + * if the first is smaller. + * If two possibilities are equally good (e.g. 512+0, + * 256+256), choose the first pair so there is more + * change-time visible (i.e. it is softer). */ int c1, c2; int tmax = msec * 9 / 8; @@ -240,9 +239,7 @@ static int choose_times(int msec, int *c1p, int *c2p) if (diff < 65536) { int actual; if (msec & 1) { - c1 = *c2p; - *c2p = *c1p; - *c1p = c1; + swap(*c2p, *c1p); } actual = time_codes[*c1p] + time_codes[*c2p]; if (*c1p < *c2p) @@ -255,8 +252,8 @@ static int choose_times(int msec, int *c1p, int *c2p) } /* - * Update the register file with the appropriate 3-bit state for - * the given led. + * Update the register file with the appropriate 3-bit state for the + * given led. */ static void set_select(struct tca6507_chip *tca, int led, int val) { @@ -274,9 +271,9 @@ static void set_select(struct tca6507_chip *tca, int led, int val) } } -/* Update the register file with the appropriate 4-bit code for - * one bank or other. This can be used for timers, for levels, or - * for initialisation. +/* Update the register file with the appropriate 4-bit code for one + * bank or other. This can be used for timers, for levels, or for + * initialization. */ static void set_code(struct tca6507_chip *tca, int reg, int bank, int new) { @@ -309,15 +306,18 @@ static void set_level(struct tca6507_chip *tca, int bank, int level) tca->bank[bank].level = level; } -/* Record all relevant time code for a given bank */ +/* Record all relevant time codes for a given bank */ static void set_times(struct tca6507_chip *tca, int bank) { int c1, c2; int result; result = choose_times(tca->bank[bank].ontime, &c1, &c2); + if (result < 0) + return; dev_dbg(&tca->client->dev, - "Chose on times %d(%d) %d(%d) for %dms\n", c1, time_codes[c1], + "Chose on times %d(%d) %d(%d) for %dms\n", + c1, time_codes[c1], c2, time_codes[c2], tca->bank[bank].ontime); set_code(tca, TCA6507_FADE_ON, bank, c2); set_code(tca, TCA6507_FULL_ON, bank, c1); @@ -325,7 +325,8 @@ static void set_times(struct tca6507_chip *tca, int bank) result = choose_times(tca->bank[bank].offtime, &c1, &c2); dev_dbg(&tca->client->dev, - "Chose off times %d(%d) %d(%d) for %dms\n", c1, time_codes[c1], + "Chose off times %d(%d) %d(%d) for %dms\n", + c1, time_codes[c1], c2, time_codes[c2], tca->bank[bank].offtime); set_code(tca, TCA6507_FADE_OFF, bank, c2); set_code(tca, TCA6507_FIRST_OFF, bank, c1); @@ -373,7 +374,8 @@ static void led_release(struct tca6507_led *led) static int led_prepare(struct tca6507_led *led) { - /* Assign this led to a bank, configuring that bank if necessary. */ + /* Assign this led to a bank, configuring that bank if + * necessary. */ int level = TO_LEVEL(led->led_cdev.brightness); struct tca6507_chip *tca = led->chip; int c1, c2; @@ -389,10 +391,10 @@ static int led_prepare(struct tca6507_led *led) if (led->ontime == 0 || led->offtime == 0) { /* - * Just set the brightness, choosing first usable bank. - * If none perfect, choose best. - * Count backwards so we check MASTER bank first - * to avoid wasting a timer. + * Just set the brightness, choosing first usable + * bank. If none perfect, choose best. Count + * backwards so we check MASTER bank first to avoid + * wasting a timer. */ int best = -1;/* full-on */ int diff = 15-level; @@ -433,9 +435,9 @@ static int led_prepare(struct tca6507_led *led) } /* - * We have on/off time so we need to try to allocate a timing bank. - * First check if times are compatible with hardware and give up if - * not. + * We have on/off time so we need to try to allocate a timing + * bank. First check if times are compatible with hardware + * and give up if not. */ if (choose_times(led->ontime, &c1, &c2) < 0) return -EINVAL; @@ -523,8 +525,8 @@ static int led_assign(struct tca6507_led *led) err = led_prepare(led); if (err) { /* - * Can only fail on timer setup. In that case we need to - * re-establish as steady level. + * Can only fail on timer setup. In that case we need + * to re-establish as steady level. */ led->ontime = 0; led->offtime = 0; @@ -586,32 +588,33 @@ static int tca6507_blink_set(struct led_classdev *led_cdev, } #ifdef CONFIG_GPIOLIB -static void tca6507_gpio_set_value(struct gpio_chip *gc, - unsigned offset, int val) +static int tca6507_gpio_set_value(struct gpio_chip *gc, unsigned int offset, + int val) { - struct tca6507_chip *tca = container_of(gc, struct tca6507_chip, gpio); + struct tca6507_chip *tca = gpiochip_get_data(gc); unsigned long flags; spin_lock_irqsave(&tca->lock, flags); /* - * 'OFF' is floating high, and 'ON' is pulled down, so it has the - * inverse sense of 'val'. + * 'OFF' is floating high, and 'ON' is pulled down, so it has + * the inverse sense of 'val'. */ set_select(tca, tca->gpio_map[offset], val ? TCA6507_LS_LED_OFF : TCA6507_LS_LED_ON); spin_unlock_irqrestore(&tca->lock, flags); if (tca->reg_set) schedule_work(&tca->work); + + return 0; } static int tca6507_gpio_direction_output(struct gpio_chip *gc, unsigned offset, int val) { - tca6507_gpio_set_value(gc, offset, val); - return 0; + return tca6507_gpio_set_value(gc, offset, val); } -static int tca6507_probe_gpios(struct i2c_client *client, +static int tca6507_probe_gpios(struct device *dev, struct tca6507_chip *tca, struct tca6507_platform_data *pdata) { @@ -622,7 +625,6 @@ static int tca6507_probe_gpios(struct i2c_client *client, for (i = 0; i < NUM_LEDS; i++) if (pdata->leds.leds[i].name && pdata->leds.leds[i].flags) { /* Configure as a gpio */ - tca->gpio_name[gpios] = pdata->leds.leds[i].name; tca->gpio_map[gpios] = i; gpios++; } @@ -631,126 +633,104 @@ static int tca6507_probe_gpios(struct i2c_client *client, return 0; tca->gpio.label = "gpio-tca6507"; - tca->gpio.names = tca->gpio_name; tca->gpio.ngpio = gpios; - tca->gpio.base = pdata->gpio_base; + tca->gpio.base = -1; tca->gpio.owner = THIS_MODULE; tca->gpio.direction_output = tca6507_gpio_direction_output; tca->gpio.set = tca6507_gpio_set_value; - tca->gpio.dev = &client->dev; - err = gpiochip_add(&tca->gpio); + tca->gpio.parent = dev; + err = devm_gpiochip_add_data(dev, &tca->gpio, tca); if (err) { tca->gpio.ngpio = 0; return err; } - if (pdata->setup) - pdata->setup(tca->gpio.base, tca->gpio.ngpio); return 0; } - -static void tca6507_remove_gpio(struct tca6507_chip *tca) -{ - if (tca->gpio.ngpio) { - int err = gpiochip_remove(&tca->gpio); - dev_err(&tca->client->dev, "%s failed, %d\n", - "gpiochip_remove()", err); - } -} #else /* CONFIG_GPIOLIB */ -static int tca6507_probe_gpios(struct i2c_client *client, +static int tca6507_probe_gpios(struct device *dev, struct tca6507_chip *tca, struct tca6507_platform_data *pdata) { return 0; } -static void tca6507_remove_gpio(struct tca6507_chip *tca) -{ -} #endif /* CONFIG_GPIOLIB */ -#ifdef CONFIG_OF static struct tca6507_platform_data * -tca6507_led_dt_init(struct i2c_client *client) +tca6507_led_dt_init(struct device *dev) { - struct device_node *np = client->dev.of_node, *child; struct tca6507_platform_data *pdata; struct led_info *tca_leds; int count; - count = of_get_child_count(np); + count = device_get_child_node_count(dev); if (!count || count > NUM_LEDS) return ERR_PTR(-ENODEV); - tca_leds = devm_kzalloc(&client->dev, - sizeof(struct led_info) * count, GFP_KERNEL); + tca_leds = devm_kcalloc(dev, NUM_LEDS, sizeof(struct led_info), + GFP_KERNEL); if (!tca_leds) return ERR_PTR(-ENOMEM); - for_each_child_of_node(np, child) { + device_for_each_child_node_scoped(dev, child) { struct led_info led; u32 reg; int ret; - led.name = - of_get_property(child, "label", NULL) ? : child->name; - led.default_trigger = - of_get_property(child, "linux,default-trigger", NULL); + if (fwnode_property_read_string(child, "label", &led.name)) + led.name = fwnode_get_name(child); - ret = of_property_read_u32(child, "reg", ®); - if (ret != 0) - continue; + if (fwnode_property_read_string(child, "linux,default-trigger", + &led.default_trigger)) + led.default_trigger = NULL; + + led.flags = 0; + if (fwnode_device_is_compatible(child, "gpio")) + led.flags |= TCA6507_MAKE_GPIO; + + ret = fwnode_property_read_u32(child, "reg", ®); + if (ret || reg >= NUM_LEDS) + return ERR_PTR(ret ? : -EINVAL); tca_leds[reg] = led; } - pdata = devm_kzalloc(&client->dev, - sizeof(struct tca6507_platform_data), GFP_KERNEL); + + pdata = devm_kzalloc(dev, sizeof(struct tca6507_platform_data), + GFP_KERNEL); if (!pdata) return ERR_PTR(-ENOMEM); pdata->leds.leds = tca_leds; - pdata->leds.num_leds = count; + pdata->leds.num_leds = NUM_LEDS; return pdata; } -static const struct of_device_id of_tca6507_leds_match[] = { +static const struct of_device_id __maybe_unused of_tca6507_leds_match[] = { { .compatible = "ti,tca6507", }, {}, }; +MODULE_DEVICE_TABLE(of, of_tca6507_leds_match); -#else -static struct tca6507_platform_data * -tca6507_led_dt_init(struct i2c_client *client) +static int tca6507_probe(struct i2c_client *client) { - return ERR_PTR(-ENODEV); -} - -#endif - -static int tca6507_probe(struct i2c_client *client, - const struct i2c_device_id *id) -{ - struct tca6507_chip *tca; + struct device *dev = &client->dev; struct i2c_adapter *adapter; + struct tca6507_chip *tca; struct tca6507_platform_data *pdata; int err; int i = 0; - adapter = to_i2c_adapter(client->dev.parent); - pdata = client->dev.platform_data; + adapter = client->adapter; if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) return -EIO; - if (!pdata || pdata->leds.num_leds != NUM_LEDS) { - pdata = tca6507_led_dt_init(client); - if (IS_ERR(pdata)) { - dev_err(&client->dev, "Need %d entries in platform-data list\n", - NUM_LEDS); - return PTR_ERR(pdata); - } + pdata = tca6507_led_dt_init(dev); + if (IS_ERR(pdata)) { + dev_err(dev, "Need %d entries in platform-data list\n", NUM_LEDS); + return PTR_ERR(pdata); } - tca = devm_kzalloc(&client->dev, sizeof(*tca), GFP_KERNEL); + tca = devm_kzalloc(dev, sizeof(*tca), GFP_KERNEL); if (!tca) return -ENOMEM; @@ -771,48 +751,31 @@ static int tca6507_probe(struct i2c_client *client, l->led_cdev.brightness_set = tca6507_brightness_set; l->led_cdev.blink_set = tca6507_blink_set; l->bank = -1; - err = led_classdev_register(&client->dev, - &l->led_cdev); + err = devm_led_classdev_register(dev, &l->led_cdev); if (err < 0) - goto exit; + return err; } } - err = tca6507_probe_gpios(client, tca, pdata); + err = tca6507_probe_gpios(dev, tca, pdata); if (err) - goto exit; + return err; /* set all registers to known state - zero */ tca->reg_set = 0x7f; schedule_work(&tca->work); return 0; -exit: - while (i--) { - if (tca->leds[i].led_cdev.name) - led_classdev_unregister(&tca->leds[i].led_cdev); - } - return err; } -static int tca6507_remove(struct i2c_client *client) +static void tca6507_remove(struct i2c_client *client) { - int i; struct tca6507_chip *tca = i2c_get_clientdata(client); - struct tca6507_led *tca_leds = tca->leds; - for (i = 0; i < NUM_LEDS; i++) { - if (tca_leds[i].led_cdev.name) - led_classdev_unregister(&tca_leds[i].led_cdev); - } - tca6507_remove_gpio(tca); cancel_work_sync(&tca->work); - - return 0; } static struct i2c_driver tca6507_driver = { .driver = { .name = "leds-tca6507", - .owner = THIS_MODULE, .of_match_table = of_match_ptr(of_tca6507_leds_match), }, .probe = tca6507_probe, |