diff options
| -rw-r--r-- | drivers/regulator/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/regulator/rpi-panel-attiny-regulator.c | 115 |
2 files changed, 98 insertions, 18 deletions
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig index 1c35fed20d34..22503e4f5327 100644 --- a/drivers/regulator/Kconfig +++ b/drivers/regulator/Kconfig @@ -984,6 +984,7 @@ config REGULATOR_RASPBERRYPI_TOUCHSCREEN_ATTINY tristate "Raspberry Pi 7-inch touchscreen panel ATTINY regulator" depends on BACKLIGHT_CLASS_DEVICE depends on I2C + depends on OF_GPIO select REGMAP_I2C help This driver supports ATTINY regulator on the Raspberry Pi 7-inch diff --git a/drivers/regulator/rpi-panel-attiny-regulator.c b/drivers/regulator/rpi-panel-attiny-regulator.c index 995915ca4a9b..998233f14085 100644 --- a/drivers/regulator/rpi-panel-attiny-regulator.c +++ b/drivers/regulator/rpi-panel-attiny-regulator.c @@ -8,6 +8,7 @@ #include <linux/backlight.h> #include <linux/err.h> #include <linux/gpio.h> +#include <linux/gpio/driver.h> #include <linux/i2c.h> #include <linux/init.h> #include <linux/interrupt.h> @@ -44,10 +45,30 @@ #define PC_RST_LCD_N BIT(2) #define PC_RST_BRIDGE_N BIT(3) +enum gpio_signals { + RST_BRIDGE_N, /* TC358762 bridge reset */ + RST_TP_N, /* Touch controller reset */ + NUM_GPIO +}; + +struct gpio_signal_mappings { + unsigned int reg; + unsigned int mask; +}; + +static const struct gpio_signal_mappings mappings[NUM_GPIO] = { + [RST_BRIDGE_N] = { REG_PORTC, PC_RST_BRIDGE_N | PC_RST_LCD_N }, + [RST_TP_N] = { REG_PORTC, PC_RST_TP_N }, +}; + struct attiny_lcd { /* lock to serialise overall accesses to the Atmel */ struct mutex lock; struct regmap *regmap; + bool gpio_states[NUM_GPIO]; + u8 port_states[3]; + + struct gpio_chip gc; }; static const struct regmap_config attiny_regmap_config = { @@ -58,6 +79,17 @@ static const struct regmap_config attiny_regmap_config = { .cache_type = REGCACHE_NONE, }; +static int attiny_set_port_state(struct attiny_lcd *state, int reg, u8 val) +{ + state->port_states[reg - REG_PORTA] = val; + return regmap_write(state->regmap, reg, val); +}; + +static u8 attiny_get_port_state(struct attiny_lcd *state, int reg) +{ + return state->port_states[reg - REG_PORTA]; +}; + static int attiny_lcd_power_enable(struct regulator_dev *rdev) { struct attiny_lcd *state = rdev_get_drvdata(rdev); @@ -65,7 +97,7 @@ static int attiny_lcd_power_enable(struct regulator_dev *rdev) mutex_lock(&state->lock); /* Ensure bridge, and tp stay in reset */ - regmap_write(rdev->regmap, REG_PORTC, 0); + attiny_set_port_state(state, REG_PORTC, 0); usleep_range(5000, 10000); /* Default to the same orientation as the closed source @@ -73,26 +105,16 @@ static int attiny_lcd_power_enable(struct regulator_dev *rdev) * configuration will be supported using VC4's plane * orientation bits. */ - regmap_write(rdev->regmap, REG_PORTA, PA_LCD_LR); + attiny_set_port_state(state, REG_PORTA, PA_LCD_LR); usleep_range(5000, 10000); - regmap_write(rdev->regmap, REG_PORTB, PB_LCD_MAIN); + /* Main regulator on, and power to the panel (LCD_VCC_N) */ + attiny_set_port_state(state, REG_PORTB, PB_LCD_MAIN); usleep_range(5000, 10000); /* Bring controllers out of reset */ - regmap_write(rdev->regmap, REG_PORTC, - PC_LED_EN | PC_RST_BRIDGE_N | PC_RST_LCD_N | PC_RST_TP_N); + attiny_set_port_state(state, REG_PORTC, PC_LED_EN); msleep(80); - regmap_write(rdev->regmap, REG_ADDR_H, 0x04); - usleep_range(5000, 8000); - regmap_write(rdev->regmap, REG_ADDR_L, 0x7c); - usleep_range(5000, 8000); - regmap_write(rdev->regmap, REG_WRITE_DATA_H, 0x00); - usleep_range(5000, 8000); - regmap_write(rdev->regmap, REG_WRITE_DATA_L, 0x00); - - msleep(100); - mutex_unlock(&state->lock); return 0; @@ -106,11 +128,12 @@ static int attiny_lcd_power_disable(struct regulator_dev *rdev) regmap_write(rdev->regmap, REG_PWM, 0); usleep_range(5000, 10000); - regmap_write(rdev->regmap, REG_PORTA, 0); + + attiny_set_port_state(state, REG_PORTA, 0); usleep_range(5000, 10000); - regmap_write(rdev->regmap, REG_PORTB, PB_LCD_VCC_N); + attiny_set_port_state(state, REG_PORTB, PB_LCD_VCC_N); usleep_range(5000, 10000); - regmap_write(rdev->regmap, REG_PORTC, 0); + attiny_set_port_state(state, REG_PORTC, 0); msleep(30); mutex_unlock(&state->lock); @@ -211,6 +234,45 @@ static const struct backlight_ops attiny_bl = { .get_brightness = attiny_get_brightness, }; +static int attiny_gpio_get_direction(struct gpio_chip *gc, unsigned int off) +{ + return GPIO_LINE_DIRECTION_OUT; +} + +static void attiny_gpio_set(struct gpio_chip *gc, unsigned int off, int val) +{ + struct attiny_lcd *state = gpiochip_get_data(gc); + u8 last_val; + + if (off >= NUM_GPIO) + return; + + mutex_lock(&state->lock); + + last_val = attiny_get_port_state(state, mappings[off].reg); + if (val) + last_val |= mappings[off].mask; + else + last_val &= ~mappings[off].mask; + + attiny_set_port_state(state, mappings[off].reg, last_val); + + if (off == RST_BRIDGE_N && val) { + usleep_range(5000, 8000); + regmap_write(state->regmap, REG_ADDR_H, 0x04); + usleep_range(5000, 8000); + regmap_write(state->regmap, REG_ADDR_L, 0x7c); + usleep_range(5000, 8000); + regmap_write(state->regmap, REG_WRITE_DATA_H, 0x00); + usleep_range(5000, 8000); + regmap_write(state->regmap, REG_WRITE_DATA_L, 0x00); + + msleep(100); + } + + mutex_unlock(&state->lock); +} + /* * I2C driver interface functions */ @@ -289,6 +351,23 @@ static int attiny_i2c_probe(struct i2c_client *i2c, bl->props.brightness = 0xff; + state->gc.parent = &i2c->dev; + state->gc.label = i2c->name; + state->gc.owner = THIS_MODULE; + state->gc.of_node = i2c->dev.of_node; + state->gc.base = -1; + state->gc.ngpio = NUM_GPIO; + + state->gc.set = attiny_gpio_set; + state->gc.get_direction = attiny_gpio_get_direction; + state->gc.can_sleep = true; + + ret = devm_gpiochip_add_data(&i2c->dev, &state->gc, state); + if (ret) { + dev_err(&i2c->dev, "Failed to create gpiochip: %d\n", ret); + goto error; + } + return 0; error: |