[PATCH v2 7/7] leds: leds-mt6323: Add support for WLEDs and MT6332

AngeloGioacchino Del Regno
2023-04-12T15:34:37Z

Add basic code to turn on and off WLEDs and wire up MT6332 support
to take advantage of it.
This is a simple approach due to to the aforementioned PMIC supporting
only on/off status so, at the time of writing, it is impossible for me
to validate more advanced functionality due to lack of hardware.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
drivers/leds/leds-mt6323.c | 171 +++++++++++++++++++++++++++++++++++--
1 file changed, 164 insertions(+), 7 deletions(-)

diff --git a/drivers/leds/leds-mt6323.c b/drivers/leds/leds-mt6323.c
index 5d95dbd9a761..202b38ac32f6 100644
--- a/drivers/leds/leds-mt6323.c
+++ b/drivers/leds/leds-mt6323.c
@@ -20,6 +20,11 @@
#define RG_DRV_32K_CK_PDN BIT(11)
#define RG_DRV_32K_CK_PDN_MASK BIT(11)

+/* 32K/1M/6M clock common for WLED device */
+#define RG_VWLED_1M_CK_PDN BIT(0)
+#define RG_VWLED_32K_CK_PDN BIT(12)
+#define RG_VWLED_6M_CK_PDN BIT(13)
+
/*
* Register field for TOP_CKPDN2 to enable
* individual clock for LED device.
@@ -73,7 +78,7 @@ struct mt6323_led {
int id;
struct mt6323_leds *parent;
struct led_classdev cdev;
- enum led_brightness current_brightness;
+ unsigned int current_brightness;
};

/**
@@ -86,6 +91,7 @@ struct mt6323_led {
* @num_isink_con: Number of ISINKx_CON registers
* @isink_max_regs: Number of ISINK[0..x] registers
* @isink_en_ctrl: Offset to ISINK_EN_CTRL register
+ * @iwled_en_ctrl: Offset to IWLED_EN_CTRL register
*/
struct mt6323_regs {
const u16 *top_ckpdn;
@@ -96,18 +102,21 @@ struct mt6323_regs {
u8 num_isink_con;
u8 isink_max_regs;
u16 isink_en_ctrl;
+ u16 iwled_en_ctrl;
};

/**
* struct mt6323_hwspec - hardware specific parameters
* @max_period: Maximum period for all LEDs
* @max_leds: Maximum number of supported LEDs
+ * @max_wleds: Maximum number of WLEDs
* @max_brightness: Maximum brightness for all LEDs
* @unit_duty: Steps of duty per period
*/
struct mt6323_hwspec {
u16 max_period;
u8 max_leds;
+ u8 max_wleds;
u16 max_brightness;
u16 unit_duty;
};
@@ -379,6 +388,117 @@ static int mt6323_led_set_brightness(struct led_classdev *cdev,
return ret;
}

+static int mtk_wled_hw_on(struct led_classdev *cdev)
+{
+ struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev);
+ struct mt6323_leds *leds = led->parent;
+ const struct mt6323_regs *regs = leds->pdata->regs;
+ struct regmap *regmap = leds->hw->regmap;
+ int ret;
+
+ ret = regmap_clear_bits(regmap, regs->top_ckpdn[0], RG_VWLED_32K_CK_PDN);
+ if (ret)
+ return ret;
+
+ ret = regmap_clear_bits(regmap, regs->top_ckpdn[0], RG_VWLED_6M_CK_PDN);
+ if (ret)
+ return ret;
+
+ ret = regmap_clear_bits(regmap, regs->top_ckpdn[0], RG_VWLED_1M_CK_PDN);
+ if (ret)
+ return ret;
+
+ usleep_range(5000, 6000);
+
+ /* Enable WLED channel pair */
+ ret = regmap_set_bits(regmap, regs->iwled_en_ctrl, BIT(led->id));
+ if (ret)
+ return ret;
+
+ ret = regmap_set_bits(regmap, regs->iwled_en_ctrl, BIT(led->id + 1));
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int mtk_wled_hw_off(struct led_classdev *cdev)
+{
+ struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev);
+ struct mt6323_leds *leds = led->parent;
+ const struct mt6323_regs *regs = leds->pdata->regs;
+ struct regmap *regmap = leds->hw->regmap;
+ int ret;
+
+ ret = regmap_clear_bits(regmap, regs->iwled_en_ctrl, BIT(led->id + 1));
+ if (ret)
+ return ret;
+
+ ret = regmap_clear_bits(regmap, regs->iwled_en_ctrl, BIT(led->id));
+ if (ret)
+ return ret;
+
+ ret = regmap_set_bits(regmap, regs->top_ckpdn[0], RG_VWLED_32K_CK_PDN);
+ if (ret)
+ return ret;
+
+ ret = regmap_set_bits(regmap, regs->top_ckpdn[0], RG_VWLED_6M_CK_PDN);
+ if (ret)
+ return ret;
+
+ ret = regmap_set_bits(regmap, regs->top_ckpdn[0], RG_VWLED_1M_CK_PDN);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static unsigned int mt6323_get_wled_brightness(struct led_classdev *cdev)
+{
+ struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev);
+ struct mt6323_leds *leds = led->parent;
+ const struct mt6323_regs *regs = leds->pdata->regs;
+ struct regmap *regmap = leds->hw->regmap;
+ unsigned int status;
+ int ret;
+
+ ret = regmap_read(regmap, regs->iwled_en_ctrl, &status);
+ if (ret)
+ return 0;
+
+ /* Always two channels per WLED */
+ status &= BIT(led->id) | BIT(led->id + 1);
+
+ return status ? led->current_brightness : 0;
+}
+
+static int mt6323_wled_set_brightness(struct led_classdev *cdev,
+ unsigned int brightness)
+{
+ struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev);
+ struct mt6323_leds *leds = led->parent;
+ int ret = 0;
+
+ mutex_lock(&leds->lock);
+
+ if (brightness) {
+ if (!led->current_brightness)
+ ret = mtk_wled_hw_on(cdev);
+ if (ret)
+ goto out;
+ } else {
+ ret = mtk_wled_hw_off(cdev);
+ if (ret)
+ goto out;
+ }
+
+ led->current_brightness = brightness;
+out:
+ mutex_unlock(&leds->lock);
+
+ return ret;
+}
+
static int mt6323_led_set_dt_default(struct led_classdev *cdev,
struct device_node *np)
{
@@ -418,6 +538,7 @@ static int mt6323_led_probe(struct platform_device *pdev)
int ret;
unsigned int status;
u32 reg;
+ u8 max_leds;

leds = devm_kzalloc(dev, sizeof(*leds), GFP_KERNEL);
if (!leds)
@@ -428,6 +549,7 @@ static int mt6323_led_probe(struct platform_device *pdev)
leds->pdata = device_get_match_data(dev);
regs = leds->pdata->regs;
spec = leds->pdata->spec;
+ max_leds = spec->max_leds + spec->max_wleds;

/*
* leds->hw points to the underlying bus for the register
@@ -447,6 +569,7 @@ static int mt6323_led_probe(struct platform_device *pdev)

for_each_available_child_of_node(np, child) {
struct led_init_data init_data = {};
+ bool is_wled;

ret = of_property_read_u32(child, "reg", &reg);
if (ret) {
@@ -454,7 +577,7 @@ static int mt6323_led_probe(struct platform_device *pdev)
goto put_child_node;
}

- if (reg >= spec->max_leds || reg >= MAX_SUPPORTED_LEDS ||
+ if (reg >= max_leds || reg >= MAX_SUPPORTED_LEDS ||
leds->led[reg]) {
dev_err(dev, "Invalid led reg %u\n", reg);
ret = -EINVAL;
@@ -467,14 +590,24 @@ static int mt6323_led_probe(struct platform_device *pdev)
goto put_child_node;
}

+ is_wled = of_property_read_bool(child, "mediatek,is-wled");
+
leds->led[reg] = led;
leds->led[reg]->id = reg;
leds->led[reg]->cdev.max_brightness = spec->max_brightness;
- leds->led[reg]->cdev.brightness_set_blocking =
- mt6323_led_set_brightness;
- leds->led[reg]->cdev.blink_set = mt6323_led_set_blink;
- leds->led[reg]->cdev.brightness_get =
- mt6323_get_led_hw_brightness;
+
+ if (is_wled) {
+ leds->led[reg]->cdev.brightness_set_blocking =
+ mt6323_wled_set_brightness;
+ leds->led[reg]->cdev.brightness_get =
+ mt6323_get_wled_brightness;
+ } else {
+ leds->led[reg]->cdev.brightness_set_blocking =
+ mt6323_led_set_brightness;
+ leds->led[reg]->cdev.blink_set = mt6323_led_set_blink;
+ leds->led[reg]->cdev.brightness_get =
+ mt6323_get_led_hw_brightness;
+ }
leds->led[reg]->parent = leds;

ret = mt6323_led_set_dt_default(&leds->led[reg]->cdev, child);
@@ -542,6 +675,17 @@ static const struct mt6323_regs mt6331_registers = {
.isink_en_ctrl = 0x43a,
};

+static const struct mt6323_regs mt6332_registers = {
+ .top_ckpdn = (const u16[]){ 0x8094, 0x809a, 0x80a0 },
+ .num_top_ckpdn = 3,
+ .top_ckcon = (const u16[]){ 0x80a6, 0x80ac },
+ .num_top_ckcon = 2,
+ .isink_con = (const u16[]){ 0x8cd4 },
+ .num_isink_con = 1,
+ .isink_max_regs = 12, /* IWLED[0..2, 3..9] */
+ .iwled_en_ctrl = 0x8cda,
+};
+
static const struct mt6323_hwspec mt6323_spec = {
.max_period = 10000,
.max_leds = 4,
@@ -549,6 +693,13 @@ static const struct mt6323_hwspec mt6323_spec = {
.unit_duty = 3125,
};

+static const struct mt6323_hwspec mt6332_spec = {
+ /* There are no LEDs in MT6332. Only WLEDs are present. */
+ .max_leds = 0,
+ .max_wleds = 1,
+ .max_brightness = 1024,
+};
+
static const struct mt6323_data mt6323_pdata = {
.regs = &mt6323_registers,
.spec = &mt6323_spec,
@@ -559,9 +710,15 @@ static const struct mt6323_data mt6331_pdata = {
.spec = &mt6323_spec,
};

+static const struct mt6323_data mt6332_pdata = {
+ .regs = &mt6332_registers,
+ .spec = &mt6332_spec,
+};
+
static const struct of_device_id mt6323_led_dt_match[] = {
{ .compatible = "mediatek,mt6323-led", .data = &mt6323_pdata},
{ .compatible = "mediatek,mt6331-led", .data = &mt6331_pdata },
+ { .compatible = "mediatek,mt6332-led", .data = &mt6332_pdata },
{},
};
MODULE_DEVICE_TABLE(of, mt6323_led_dt_match);
--
2.40.0