[PATCH V3 3/4] backlight: qcom-wled: Add support for WLED5 peripheral in PM8150L

From: Kiran Gunda
Date: Mon Mar 09 2020 - 09:27:18 EST


Add support for WLED5 peripheral that is present on PM8150L PMICs.

PM8150L WLED supports the following:
- Two modulators and each sink can use any of the modulator
- Multiple CABC selection options
- Multiple brightness width selection (12 bits to 15 bits)

Signed-off-by: Kiran Gunda <kgunda@xxxxxxxxxxxxxx>
---
.../bindings/leds/backlight/qcom-wled.yaml | 39 +++
drivers/video/backlight/qcom-wled.c | 336 ++++++++++++++++++++-
2 files changed, 374 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml
index d334f81..e0dadc4 100644
--- a/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml
+++ b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.yaml
@@ -20,6 +20,7 @@ properties:
- qcom,pm8941-wled
- qcom,pmi8998-wled
- qcom,pm660l-wled
+ - qcom,pm8150l-wled

reg:
maxItems: 1
@@ -28,10 +29,23 @@ properties:
maxItems: 1
description:
brightness value on boot, value from 0-4095.
+ For pm8150l this value vary from 0-4095 or 0-32767
+ depending on the brightness control mode. If CABC is
+ enabled 0-4095 range is used.
allOf:
- $ref: /schemas/types.yaml#/definitions/uint32
default: 2048

+ max-brightness:
+ maxItems: 1
+ description:
+ Maximum brightness level. Allowed values are,
+ for pmi8998 it is 0-4095.
+ For pm8150l, this can be either 4095 or 32767.
+ If CABC is enabled, this is capped to 4095.
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+
label:
maxItems: 1
description:
@@ -124,6 +138,31 @@ properties:
value for PM8941 from 1 to 3. Default 2
For PMI8998 from 1 to 4.

+ qcom,modulator-sel:
+ maxItems: 1
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ Selects the modulator used for brightness modulation.
+ Allowed values are,
+ 0 - Modulator A
+ 1 - Modulator B
+ If not specified, then modulator A will be used by default.
+ This property is applicable only to WLED5 peripheral.
+
+ qcom,cabc-sel:
+ maxItems: 1
+ allOf:
+ - $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ Selects the CABC pin signal used for brightness modulation.
+ Allowed values are,
+ 0 - CABC disabled
+ 1 - CABC 1
+ 2 - CABC 2
+ 3 - External signal (e.g. LPG) is used for dimming
+ This property is applicable only to WLED5 peripheral.
+
interrupts:
maxItems: 2
description:
diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index b73f273..edbbcb2 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c
@@ -19,6 +19,8 @@
#define WLED_DEFAULT_BRIGHTNESS 2048
#define WLED_SOFT_START_DLY_US 10000
#define WLED3_SINK_REG_BRIGHT_MAX 0xFFF
+#define WLED5_SINK_REG_BRIGHT_MAX_12B 0xFFF
+#define WLED5_SINK_REG_BRIGHT_MAX_15B 0x7FFF

/* WLED3/WLED4 control registers */
#define WLED3_CTRL_REG_FAULT_STATUS 0x08
@@ -40,6 +42,7 @@

#define WLED3_CTRL_REG_OVP 0x4d
#define WLED3_CTRL_REG_OVP_MASK GENMASK(1, 0)
+#define WLED5_CTRL_REG_OVP_MASK GENMASK(3, 0)

#define WLED3_CTRL_REG_ILIMIT 0x4e
#define WLED3_CTRL_REG_ILIMIT_MASK GENMASK(2, 0)
@@ -101,6 +104,40 @@

#define WLED4_SINK_REG_BRIGHT(n) (0x57 + (n * 0x10))

+/* WLED5 specific sink registers */
+#define WLED5_SINK_REG_MOD_A_EN 0x50
+#define WLED5_SINK_REG_MOD_B_EN 0x60
+#define WLED5_SINK_REG_MOD_EN_MASK BIT(7)
+
+#define WLED5_SINK_REG_MOD_A_SRC_SEL 0x51
+#define WLED5_SINK_REG_MOD_B_SRC_SEL 0x61
+#define WLED5_SINK_REG_MOD_SRC_SEL_HIGH 0
+#define WLED5_SINK_REG_MOD_SRC_SEL_EXT 0x03
+#define WLED5_SINK_REG_MOD_SRC_SEL_MASK GENMASK(1, 0)
+
+#define WLED5_SINK_REG_MOD_A_BRIGHTNESS_WIDTH_SEL 0x52
+#define WLED5_SINK_REG_MOD_B_BRIGHTNESS_WIDTH_SEL 0x62
+#define WLED5_SINK_REG_BRIGHTNESS_WIDTH_12B 0
+#define WLED5_SINK_REG_BRIGHTNESS_WIDTH_15B 1
+
+#define WLED5_SINK_REG_MOD_A_BRIGHTNESS_LSB 0x53
+#define WLED5_SINK_REG_MOD_A_BRIGHTNESS_MSB 0x54
+#define WLED5_SINK_REG_MOD_B_BRIGHTNESS_LSB 0x63
+#define WLED5_SINK_REG_MOD_B_BRIGHTNESS_MSB 0x64
+
+#define WLED5_SINK_REG_MOD_SYNC_BIT 0x65
+#define WLED5_SINK_REG_SYNC_MOD_A_BIT BIT(0)
+#define WLED5_SINK_REG_SYNC_MOD_B_BIT BIT(1)
+#define WLED5_SINK_REG_SYNC_MASK GENMASK(1, 0)
+
+/* WLED5 specific per-'string' registers below */
+#define WLED5_SINK_REG_STR_FULL_SCALE_CURR(n) (0x72 + (n * 0x10))
+
+#define WLED5_SINK_REG_STR_SRC_SEL(n) (0x73 + (n * 0x10))
+#define WLED5_SINK_REG_SRC_SEL_MOD_A 0
+#define WLED5_SINK_REG_SRC_SEL_MOD_B 1
+#define WLED5_SINK_REG_SRC_SEL_MASK GENMASK(1, 0)
+
struct wled_var_cfg {
const u32 *values;
u32 (*fn)(u32);
@@ -125,6 +162,8 @@ struct wled_config {
u32 num_strings;
u32 string_i_limit;
u32 enabled_strings[WLED_MAX_STRINGS];
+ u32 mod_sel;
+ u32 cabc_sel;
bool cs_out_en;
bool ext_gen;
bool cabc;
@@ -164,6 +203,27 @@ struct wled {
int (*wled_ovp_delay)(struct wled *wled);
};

+enum wled5_mod_sel {
+ MOD_A,
+ MOD_B,
+ MOD_MAX,
+};
+
+static const u8 wled5_brightness_reg[MOD_MAX] = {
+ [MOD_A] = WLED5_SINK_REG_MOD_A_BRIGHTNESS_LSB,
+ [MOD_B] = WLED5_SINK_REG_MOD_B_BRIGHTNESS_LSB,
+};
+
+static const u8 wled5_src_sel_reg[MOD_MAX] = {
+ [MOD_A] = WLED5_SINK_REG_MOD_A_SRC_SEL,
+ [MOD_B] = WLED5_SINK_REG_MOD_B_SRC_SEL,
+};
+
+static const u8 wled5_brt_wid_sel_reg[MOD_MAX] = {
+ [MOD_A] = WLED5_SINK_REG_MOD_A_BRIGHTNESS_WIDTH_SEL,
+ [MOD_B] = WLED5_SINK_REG_MOD_B_BRIGHTNESS_WIDTH_SEL,
+};
+
static int wled3_set_brightness(struct wled *wled, u16 brightness)
{
int rc, i;
@@ -182,6 +242,25 @@ static int wled3_set_brightness(struct wled *wled, u16 brightness)
return 0;
}

+static int wled5_set_brightness(struct wled *wled, u16 brightness)
+{
+ int rc, offset;
+ u16 low_limit = wled->max_brightness * 1 / 1000;
+ u8 v[2];
+
+ /* WLED5's lower limit is 0.1% */
+ if (brightness < low_limit)
+ brightness = low_limit;
+
+ v[0] = brightness & 0xff;
+ v[1] = (brightness >> 8) & 0x7f;
+
+ offset = wled5_brightness_reg[wled->cfg.mod_sel];
+ rc = regmap_bulk_write(wled->regmap, wled->sink_addr + offset,
+ v, 2);
+ return rc;
+}
+
static int wled4_set_brightness(struct wled *wled, u16 brightness)
{
int rc, i;
@@ -244,6 +323,24 @@ static int wled_module_enable(struct wled *wled, int val)
return 0;
}

+static int wled5_sync_toggle(struct wled *wled)
+{
+ int rc;
+ u8 val;
+
+ val = (wled->cfg.mod_sel == MOD_A) ? WLED5_SINK_REG_SYNC_MOD_A_BIT :
+ WLED5_SINK_REG_SYNC_MOD_B_BIT;
+ rc = regmap_update_bits(wled->regmap,
+ wled->sink_addr + WLED5_SINK_REG_MOD_SYNC_BIT,
+ WLED5_SINK_REG_SYNC_MASK, val);
+ if (rc < 0)
+ return rc;
+
+ return regmap_update_bits(wled->regmap,
+ wled->sink_addr + WLED5_SINK_REG_MOD_SYNC_BIT,
+ WLED5_SINK_REG_SYNC_MASK, 0);
+}
+
static int wled3_sync_toggle(struct wled *wled)
{
int rc;
@@ -345,6 +442,29 @@ static int wled_update_status(struct backlight_device *bl)
return rc;
}

+static int wled5_cabc_config(struct wled *wled, bool enable)
+{
+ int rc, offset;
+ u8 reg;
+
+ if (wled->cabc_disabled)
+ return 0;
+
+ reg = enable ? wled->cfg.cabc_sel : 0;
+ offset = wled5_src_sel_reg[wled->cfg.mod_sel];
+ rc = regmap_update_bits(wled->regmap, wled->sink_addr + offset,
+ WLED5_SINK_REG_MOD_SRC_SEL_MASK, reg);
+ if (rc < 0) {
+ pr_err("Error in configuring CABC rc=%d\n", rc);
+ return rc;
+ }
+
+ if (!wled->cfg.cabc_sel)
+ wled->cabc_disabled = true;
+
+ return 0;
+}
+
static int wled4_cabc_config(struct wled *wled, bool enable)
{
int i, j, rc;
@@ -909,6 +1029,115 @@ static const struct wled_config wled4_config_defaults = {
.auto_detection_enabled = false,
};

+static int wled5_setup(struct wled *wled)
+{
+ int rc, temp, i, j;
+ u8 sink_en = 0;
+ u16 addr;
+ u32 val;
+
+ rc = regmap_update_bits(wled->regmap,
+ wled->ctrl_addr + WLED3_CTRL_REG_OVP,
+ WLED5_CTRL_REG_OVP_MASK, wled->cfg.ovp);
+ if (rc < 0)
+ return rc;
+
+ rc = regmap_update_bits(wled->regmap,
+ wled->ctrl_addr + WLED3_CTRL_REG_ILIMIT,
+ WLED3_CTRL_REG_ILIMIT_MASK,
+ wled->cfg.boost_i_limit);
+ if (rc < 0)
+ return rc;
+
+ rc = regmap_update_bits(wled->regmap,
+ wled->ctrl_addr + WLED3_CTRL_REG_FREQ,
+ WLED3_CTRL_REG_FREQ_MASK,
+ wled->cfg.switch_freq);
+ if (rc < 0)
+ return rc;
+
+ /* Per sink/string configuration */
+ for (i = 0; i < wled->cfg.num_strings; ++i) {
+ j = wled->cfg.enabled_strings[i];
+ addr = wled->sink_addr +
+ WLED4_SINK_REG_STR_FULL_SCALE_CURR(j);
+ rc = regmap_update_bits(wled->regmap, addr,
+ WLED4_SINK_REG_STR_FULL_SCALE_CURR_MASK,
+ wled->cfg.string_i_limit);
+ if (rc < 0)
+ return rc;
+
+ addr = wled->sink_addr + WLED5_SINK_REG_STR_SRC_SEL(j);
+ rc = regmap_update_bits(wled->regmap, addr,
+ WLED5_SINK_REG_SRC_SEL_MASK,
+ wled->cfg.mod_sel == MOD_A ?
+ WLED5_SINK_REG_SRC_SEL_MOD_A :
+ WLED5_SINK_REG_SRC_SEL_MOD_B);
+
+ temp = j + WLED4_SINK_REG_CURR_SINK_SHFT;
+ sink_en |= 1 << temp;
+ }
+
+ rc = wled5_cabc_config(wled, wled->cfg.cabc_sel ? true : false);
+ if (rc < 0)
+ return rc;
+
+ /* Enable one of the modulators A or B based on mod_sel */
+ addr = wled->sink_addr + WLED5_SINK_REG_MOD_A_EN;
+ val = (wled->cfg.mod_sel == MOD_A) ? WLED5_SINK_REG_MOD_EN_MASK : 0;
+ rc = regmap_update_bits(wled->regmap, addr,
+ WLED5_SINK_REG_MOD_EN_MASK, val);
+ if (rc < 0)
+ return rc;
+
+ addr = wled->sink_addr + WLED5_SINK_REG_MOD_B_EN;
+ val = (wled->cfg.mod_sel == MOD_B) ? WLED5_SINK_REG_MOD_EN_MASK : 0;
+ rc = regmap_update_bits(wled->regmap, addr,
+ WLED5_SINK_REG_MOD_EN_MASK, val);
+ if (rc < 0)
+ return rc;
+
+ addr = wled->sink_addr + wled5_brt_wid_sel_reg[wled->cfg.mod_sel];
+ val = (wled->max_brightness == WLED5_SINK_REG_BRIGHT_MAX_15B) ?
+ WLED5_SINK_REG_BRIGHTNESS_WIDTH_15B :
+ WLED5_SINK_REG_BRIGHTNESS_WIDTH_12B;
+ rc = regmap_write(wled->regmap, addr, val);
+ if (rc < 0)
+ return rc;
+
+ rc = regmap_update_bits(wled->regmap,
+ wled->sink_addr + WLED4_SINK_REG_CURR_SINK,
+ WLED4_SINK_REG_CURR_SINK_MASK, sink_en);
+ if (rc < 0)
+ return rc;
+
+ /* This updates only FSC configuration in WLED5 */
+ rc = wled->wled_sync_toggle(wled);
+ if (rc < 0) {
+ pr_err("Failed to toggle sync reg rc:%d\n", rc);
+ return rc;
+ }
+
+ rc = wled_auto_detection_at_init(wled);
+ if (rc < 0)
+ return rc;
+
+ return 0;
+}
+
+static const struct wled_config wled5_config_defaults = {
+ .boost_i_limit = 5,
+ .string_i_limit = 10,
+ .ovp = 4,
+ .num_strings = 4,
+ .switch_freq = 11,
+ .mod_sel = 0,
+ .cabc_sel = 0,
+ .cabc = false,
+ .external_pfet = false,
+ .auto_detection_enabled = false,
+};
+
static const u32 wled3_boost_i_limit_values[] = {
105, 385, 525, 805, 980, 1260, 1400, 1680,
};
@@ -927,6 +1156,16 @@ static const struct wled_var_cfg wled4_boost_i_limit_cfg = {
.size = ARRAY_SIZE(wled4_boost_i_limit_values),
};

+static inline u32 wled5_boost_i_limit_values_fn(u32 idx)
+{
+ return 525 + (idx * 175);
+}
+
+static const struct wled_var_cfg wled5_boost_i_limit_cfg = {
+ .fn = wled5_boost_i_limit_values_fn,
+ .size = 8,
+};
+
static const u32 wled3_ovp_values[] = {
35, 32, 29, 27,
};
@@ -945,6 +1184,21 @@ static const struct wled_var_cfg wled4_ovp_cfg = {
.size = ARRAY_SIZE(wled4_ovp_values),
};

+static inline u32 wled5_ovp_values_fn(u32 idx)
+{
+ /*
+ * 0000 - 38.5 V
+ * 0001 - 37 V ..
+ * 1111 - 16 V
+ */
+ return 38500 - (idx * 1500);
+}
+
+static const struct wled_var_cfg wled5_ovp_cfg = {
+ .fn = wled5_ovp_values_fn,
+ .size = 16,
+};
+
static u32 wled3_num_strings_values_fn(u32 idx)
{
return idx + 1;
@@ -992,6 +1246,14 @@ static const struct wled_var_cfg wled4_string_cfg = {
.size = 16,
};

+static const struct wled_var_cfg wled5_mod_sel_cfg = {
+ .size = 2,
+};
+
+static const struct wled_var_cfg wled5_cabc_sel_cfg = {
+ .size = 4,
+};
+
static u32 wled_values(const struct wled_var_cfg *cfg, u32 idx)
{
if (idx >= cfg->size)
@@ -1068,6 +1330,44 @@ static int wled_configure(struct wled *wled)
},
};

+ const struct wled_u32_opts wled5_opts[] = {
+ {
+ .name = "qcom,current-boost-limit",
+ .val_ptr = &cfg->boost_i_limit,
+ .cfg = &wled5_boost_i_limit_cfg,
+ },
+ {
+ .name = "qcom,current-limit-microamp",
+ .val_ptr = &cfg->string_i_limit,
+ .cfg = &wled4_string_i_limit_cfg,
+ },
+ {
+ .name = "qcom,ovp-millivolt",
+ .val_ptr = &cfg->ovp,
+ .cfg = &wled5_ovp_cfg,
+ },
+ {
+ .name = "qcom,switching-freq",
+ .val_ptr = &cfg->switch_freq,
+ .cfg = &wled3_switch_freq_cfg,
+ },
+ {
+ .name = "qcom,num-strings",
+ .val_ptr = &cfg->num_strings,
+ .cfg = &wled4_num_strings_cfg,
+ },
+ {
+ .name = "qcom,modulator-sel",
+ .val_ptr = &cfg->mod_sel,
+ .cfg = &wled5_mod_sel_cfg,
+ },
+ {
+ .name = "qcom,cabc-sel",
+ .val_ptr = &cfg->cabc_sel,
+ .cfg = &wled5_cabc_sel_cfg,
+ },
+ };
+
const struct wled_bool_opts bool_opts[] = {
{ "qcom,cs-out", &cfg->cs_out_en, },
{ "qcom,ext-gen", &cfg->ext_gen, },
@@ -1117,6 +1417,23 @@ static int wled_configure(struct wled *wled)
wled->sink_addr = be32_to_cpu(*prop_addr);
break;

+ case 5:
+ u32_opts = wled5_opts;
+ size = ARRAY_SIZE(wled5_opts);
+ *cfg = wled5_config_defaults;
+ wled->wled_set_brightness = wled5_set_brightness;
+ wled->wled_sync_toggle = wled5_sync_toggle;
+ wled->cabc_config = wled5_cabc_config;
+ wled->max_string_count = 4;
+
+ prop_addr = of_get_address(dev->of_node, 1, NULL, NULL);
+ if (!prop_addr) {
+ dev_err(wled->dev, "invalid IO resources\n");
+ return -EINVAL;
+ }
+ wled->sink_addr = be32_to_cpu(*prop_addr);
+ break;
+
default:
dev_err(wled->dev, "Invalid WLED version\n");
return -EINVAL;
@@ -1270,6 +1587,10 @@ static int wled_probe(struct platform_device *pdev)
if (rc)
return rc;

+ val = WLED3_SINK_REG_BRIGHT_MAX;
+ of_property_read_u32(pdev->dev.of_node, "max-brightness", &val);
+ wled->max_brightness = val;
+
switch (wled->version) {
case 3:
wled->cfg.auto_detection_enabled = false;
@@ -1289,6 +1610,18 @@ static int wled_probe(struct platform_device *pdev)
}
break;

+ case 5:
+ wled->has_short_detect = true;
+ if (wled->cfg.cabc_sel)
+ wled->max_brightness = WLED5_SINK_REG_BRIGHT_MAX_12B;
+
+ rc = wled5_setup(wled);
+ if (rc) {
+ dev_err(&pdev->dev, "wled5_setup failed\n");
+ return rc;
+ }
+ break;
+
default:
dev_err(wled->dev, "Invalid WLED version\n");
break;
@@ -1310,7 +1643,7 @@ static int wled_probe(struct platform_device *pdev)
memset(&props, 0, sizeof(struct backlight_properties));
props.type = BACKLIGHT_RAW;
props.brightness = val;
- props.max_brightness = WLED3_SINK_REG_BRIGHT_MAX;
+ props.max_brightness = wled->max_brightness;
bl = devm_backlight_device_register(&pdev->dev, wled->name,
&pdev->dev, wled,
&wled_ops, &props);
@@ -1333,6 +1666,7 @@ static const struct of_device_id wled_match_table[] = {
{ .compatible = "qcom,pm8941-wled", .data = (void *)3 },
{ .compatible = "qcom,pmi8998-wled", .data = (void *)4 },
{ .compatible = "qcom,pm660l-wled", .data = (void *)4 },
+ { .compatible = "qcom,pm8150l-wled", .data = (void *)5 },
{}
};
MODULE_DEVICE_TABLE(of, wled_match_table);
--
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