diff options
Diffstat (limited to 'drivers/regulator')
-rw-r--r-- | drivers/regulator/rpi-panel-attiny-regulator.c | 91 |
1 files changed, 80 insertions, 11 deletions
diff --git a/drivers/regulator/rpi-panel-attiny-regulator.c b/drivers/regulator/rpi-panel-attiny-regulator.c index 00fb69efcfa2..a4af7adad2b5 100644 --- a/drivers/regulator/rpi-panel-attiny-regulator.c +++ b/drivers/regulator/rpi-panel-attiny-regulator.c @@ -27,18 +27,28 @@ #define REG_POWERON 0x85 #define REG_PWM 0x86 +struct attiny_lcd { + /* lock to serialise overall accesses to the Atmel */ + struct mutex lock; + struct regmap *regmap; +}; + static const struct regmap_config attiny_regmap_config = { .reg_bits = 8, .val_bits = 8, + .disable_locking = 1, .max_register = REG_PWM, .cache_type = REGCACHE_NONE, }; static int attiny_lcd_power_enable(struct regulator_dev *rdev) { + struct mutex *lock = rdev_get_drvdata(rdev); unsigned int data; int ret, i; + mutex_lock(lock); + regmap_write(rdev->regmap, REG_POWERON, 1); msleep(80); @@ -63,33 +73,49 @@ static int attiny_lcd_power_enable(struct regulator_dev *rdev) */ regmap_write(rdev->regmap, REG_PORTA, BIT(2)); + mutex_unlock(lock); + return 0; } static int attiny_lcd_power_disable(struct regulator_dev *rdev) { + struct mutex *lock = rdev_get_drvdata(rdev); + + mutex_lock(lock); + regmap_write(rdev->regmap, REG_PWM, 0); regmap_write(rdev->regmap, REG_POWERON, 0); msleep(30); + + mutex_unlock(lock); + return 0; } static int attiny_lcd_power_is_enabled(struct regulator_dev *rdev) { + struct mutex *lock = rdev_get_drvdata(rdev); unsigned int data; int ret, i; + mutex_lock(lock); + for (i = 0; i < 10; i++) { ret = regmap_read(rdev->regmap, REG_POWERON, &data); if (!ret) break; usleep_range(10000, 12000); } - if (ret < 0) + if (ret < 0) { + mutex_unlock(lock); return ret; + } - if (!(data & BIT(0))) + if (!(data & BIT(0))) { + mutex_unlock(lock); return 0; + } for (i = 0; i < 10; i++) { ret = regmap_read(rdev->regmap, REG_PORTB, &data); @@ -98,6 +124,8 @@ static int attiny_lcd_power_is_enabled(struct regulator_dev *rdev) usleep_range(10000, 12000); } + mutex_unlock(lock); + if (ret < 0) return ret; @@ -125,10 +153,13 @@ static const struct regulator_desc attiny_regulator = { static int attiny_update_status(struct backlight_device *bl) { - struct regmap *regmap = bl_get_data(bl); + struct attiny_lcd *state = bl_get_data(bl); + struct regmap *regmap = state->regmap; int brightness = bl->props.brightness; int ret, i; + mutex_lock(&state->lock); + if (bl->props.power != FB_BLANK_UNBLANK || bl->props.fb_blank != FB_BLANK_UNBLANK) brightness = 0; @@ -139,20 +170,27 @@ static int attiny_update_status(struct backlight_device *bl) break; } + mutex_unlock(&state->lock); + return ret; } static int attiny_get_brightness(struct backlight_device *bl) { - struct regmap *regmap = bl_get_data(bl); + struct attiny_lcd *state = bl_get_data(bl); + struct regmap *regmap = state->regmap; int ret, brightness, i; + mutex_lock(&state->lock); + for (i = 0; i < 10; i++) { ret = regmap_read(regmap, REG_PWM, &brightness); if (!ret) break; } + mutex_unlock(&state->lock); + if (ret) return ret; @@ -174,22 +212,30 @@ static int attiny_i2c_probe(struct i2c_client *i2c, struct regulator_config config = { }; struct backlight_device *bl; struct regulator_dev *rdev; + struct attiny_lcd *state; struct regmap *regmap; unsigned int data; int ret; + state = devm_kzalloc(&i2c->dev, sizeof(*state), GFP_KERNEL); + if (!state) + return -ENOMEM; + + mutex_init(&state->lock); + i2c_set_clientdata(i2c, state); + regmap = devm_regmap_init_i2c(i2c, &attiny_regmap_config); if (IS_ERR(regmap)) { ret = PTR_ERR(regmap); dev_err(&i2c->dev, "Failed to allocate register map: %d\n", ret); - return ret; + goto error; } ret = regmap_read(regmap, REG_ID, &data); if (ret < 0) { dev_err(&i2c->dev, "Failed to read REG_ID reg: %d\n", ret); - return ret; + goto error; } switch (data) { @@ -198,7 +244,8 @@ static int attiny_i2c_probe(struct i2c_client *i2c, break; default: dev_err(&i2c->dev, "Unknown Atmel firmware revision: 0x%02x\n", data); - return -ENODEV; + ret = -ENODEV; + goto error; } regmap_write(regmap, REG_POWERON, 0); @@ -208,24 +255,45 @@ static int attiny_i2c_probe(struct i2c_client *i2c, config.regmap = regmap; config.of_node = i2c->dev.of_node; config.init_data = &attiny_regulator_default; + config.driver_data = &state->lock; rdev = devm_regulator_register(&i2c->dev, &attiny_regulator, &config); if (IS_ERR(rdev)) { dev_err(&i2c->dev, "Failed to register ATTINY regulator\n"); - return PTR_ERR(rdev); + ret = PTR_ERR(rdev); + goto error; } props.type = BACKLIGHT_RAW; props.max_brightness = 0xff; + + state->regmap = regmap; + bl = devm_backlight_device_register(&i2c->dev, dev_name(&i2c->dev), - &i2c->dev, regmap, &attiny_bl, + &i2c->dev, state, &attiny_bl, &props); - if (IS_ERR(bl)) - return PTR_ERR(bl); + if (IS_ERR(bl)) { + ret = PTR_ERR(bl); + goto error; + } bl->props.brightness = 0xff; return 0; + +error: + mutex_destroy(&state->lock); + + return ret; +} + +static int attiny_i2c_remove(struct i2c_client *client) +{ + struct attiny_lcd *state = i2c_get_clientdata(client); + + mutex_destroy(&state->lock); + + return 0; } static const struct of_device_id attiny_dt_ids[] = { @@ -240,6 +308,7 @@ static struct i2c_driver attiny_regulator_driver = { .of_match_table = of_match_ptr(attiny_dt_ids), }, .probe = attiny_i2c_probe, + .remove = attiny_i2c_remove, }; module_i2c_driver(attiny_regulator_driver); |