From 3cf717e1b077749001602a141dcdc2151e8307e1 Mon Sep 17 00:00:00 2001 From: Dave Stevenson Date: Thu, 9 Sep 2021 18:24:57 +0100 Subject: [PATCH] regulator: rpi-panel: Convert to drive lines directly The Atmel was doing a load of automatic sequencing of control lines, however it was combining the touch controller's reset with the bridge/panel control. Change to control the control signals directly rather than through the automatic POWERON control. Signed-off-by: Dave Stevenson --- .../regulator/rpi-panel-attiny-regulator.c | 111 ++++++++++-------- 1 file changed, 60 insertions(+), 51 deletions(-) --- a/drivers/regulator/rpi-panel-attiny-regulator.c +++ b/drivers/regulator/rpi-panel-attiny-regulator.c @@ -21,11 +21,28 @@ /* I2C registers of the Atmel microcontroller. */ #define REG_ID 0x80 #define REG_PORTA 0x81 -#define REG_PORTA_HF BIT(2) -#define REG_PORTA_VF BIT(3) #define REG_PORTB 0x82 +#define REG_PORTC 0x83 #define REG_POWERON 0x85 #define REG_PWM 0x86 +#define REG_ADDR_L 0x8c +#define REG_ADDR_H 0x8d +#define REG_WRITE_DATA_H 0x90 +#define REG_WRITE_DATA_L 0x91 + +#define PA_LCD_DITHB BIT(0) +#define PA_LCD_MODE BIT(1) +#define PA_LCD_LR BIT(2) +#define PA_LCD_UD BIT(3) + +#define PB_BRIDGE_PWRDNX_N BIT(0) +#define PB_LCD_VCC_N BIT(1) +#define PB_LCD_MAIN BIT(7) + +#define PC_LED_EN BIT(0) +#define PC_RST_TP_N BIT(1) +#define PC_RST_LCD_N BIT(2) +#define PC_RST_BRIDGE_N BIT(3) struct attiny_lcd { /* lock to serialise overall accesses to the Atmel */ @@ -37,99 +54,91 @@ static const struct regmap_config attiny .reg_bits = 8, .val_bits = 8, .disable_locking = 1, - .max_register = REG_PWM, + .max_register = REG_WRITE_DATA_L, .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; + struct attiny_lcd *state = rdev_get_drvdata(rdev); - mutex_lock(lock); - - regmap_write(rdev->regmap, REG_POWERON, 1); - msleep(80); + mutex_lock(&state->lock); - /* Wait for nPWRDWN to go low to indicate poweron is done. */ - for (i = 0; i < 20; i++) { - ret = regmap_read(rdev->regmap, REG_PORTB, &data); - if (!ret) { - if (data & BIT(0)) - break; - } - usleep_range(10000, 12000); - } - usleep_range(10000, 12000); - - if (ret) - pr_err("%s: regmap_read_poll_timeout failed %d\n", __func__, ret); + /* Ensure bridge, and tp stay in reset */ + regmap_write(rdev->regmap, REG_PORTC, 0); + usleep_range(5000, 10000); /* Default to the same orientation as the closed source * firmware used for the panel. Runtime rotation * configuration will be supported using VC4's plane * orientation bits. */ - regmap_write(rdev->regmap, REG_PORTA, BIT(2)); + regmap_write(rdev->regmap, REG_PORTA, PA_LCD_LR); + usleep_range(5000, 10000); + regmap_write(rdev->regmap, 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); + + 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); - mutex_unlock(lock); + msleep(100); + + mutex_unlock(&state->lock); return 0; } static int attiny_lcd_power_disable(struct regulator_dev *rdev) { - struct mutex *lock = rdev_get_drvdata(rdev); + struct attiny_lcd *state = rdev_get_drvdata(rdev); - mutex_lock(lock); + mutex_lock(&state->lock); regmap_write(rdev->regmap, REG_PWM, 0); - regmap_write(rdev->regmap, REG_POWERON, 0); + usleep_range(5000, 10000); + regmap_write(rdev->regmap, REG_PORTA, 0); + usleep_range(5000, 10000); + regmap_write(rdev->regmap, REG_PORTB, PB_LCD_VCC_N); + usleep_range(5000, 10000); + regmap_write(rdev->regmap, REG_PORTC, 0); msleep(30); - mutex_unlock(lock); + mutex_unlock(&state->lock); return 0; } static int attiny_lcd_power_is_enabled(struct regulator_dev *rdev) { - struct mutex *lock = rdev_get_drvdata(rdev); + struct attiny_lcd *state = 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) { - mutex_unlock(lock); - return ret; - } - - if (!(data & BIT(0))) { - mutex_unlock(lock); - return 0; - } + mutex_lock(&state->lock); for (i = 0; i < 10; i++) { - ret = regmap_read(rdev->regmap, REG_PORTB, &data); + ret = regmap_read(rdev->regmap, REG_PORTC, &data); if (!ret) break; usleep_range(10000, 12000); } - mutex_unlock(lock); + mutex_unlock(&state->lock); if (ret < 0) return ret; - return data & BIT(0); + return data & PC_RST_BRIDGE_N; } static const struct regulator_init_data attiny_regulator_default = { @@ -256,7 +265,7 @@ static int attiny_i2c_probe(struct i2c_c config.regmap = regmap; config.of_node = i2c->dev.of_node; config.init_data = &attiny_regulator_default; - config.driver_data = &state->lock; + config.driver_data = state; rdev = devm_regulator_register(&i2c->dev, &attiny_regulator, &config); if (IS_ERR(rdev)) {