[PATCH V9 4/6] backlight: qcom-wled: Add support for WLED4 peripheral.

From: Kiran Gunda
Date: Wed Oct 23 2019 - 03:07:57 EST


WLED4 peripheral is present on some PMICs like pmi8998 and
pm660l. It has a different register map and configurations
are also different. Add support for it.

Signed-off-by: Kiran Gunda <kgunda@xxxxxxxxxxxxxx>
Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Reviewed-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>
---
drivers/video/backlight/qcom-wled.c | 255 +++++++++++++++++++++++++++++++++++-
1 file changed, 253 insertions(+), 2 deletions(-)

diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index 45eeda4..5386ca9 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c
@@ -17,7 +17,7 @@

#define WLED3_SINK_REG_BRIGHT_MAX 0xFFF

-/* WLED3 control registers */
+/* WLED3/WLED4 control registers */
#define WLED3_CTRL_REG_MOD_EN 0x46
#define WLED3_CTRL_REG_MOD_EN_MASK BIT(7)
#define WLED3_CTRL_REG_MOD_EN_SHIFT 7
@@ -31,7 +31,7 @@
#define WLED3_CTRL_REG_ILIMIT 0x4e
#define WLED3_CTRL_REG_ILIMIT_MASK GENMASK(2, 0)

-/* WLED3 sink registers */
+/* WLED3/WLED4 sink registers */
#define WLED3_SINK_REG_SYNC 0x47
#define WLED3_SINK_REG_SYNC_CLEAR 0x00

@@ -56,6 +56,28 @@
#define WLED3_SINK_REG_STR_CABC(n) (0x66 + (n * 0x10))
#define WLED3_SINK_REG_STR_CABC_MASK BIT(7)

+/* WLED4 specific sink registers */
+#define WLED4_SINK_REG_CURR_SINK 0x46
+#define WLED4_SINK_REG_CURR_SINK_MASK GENMASK(7, 4)
+#define WLED4_SINK_REG_CURR_SINK_SHFT 4
+
+/* WLED4 specific per-'string' registers below */
+#define WLED4_SINK_REG_STR_MOD_EN(n) (0x50 + (n * 0x10))
+#define WLED4_SINK_REG_STR_MOD_MASK BIT(7)
+
+#define WLED4_SINK_REG_STR_FULL_SCALE_CURR(n) (0x52 + (n * 0x10))
+#define WLED4_SINK_REG_STR_FULL_SCALE_CURR_MASK GENMASK(3, 0)
+
+#define WLED4_SINK_REG_STR_MOD_SRC(n) (0x53 + (n * 0x10))
+#define WLED4_SINK_REG_STR_MOD_SRC_MASK BIT(0)
+#define WLED4_SINK_REG_STR_MOD_SRC_INT 0x00
+#define WLED4_SINK_REG_STR_MOD_SRC_EXT 0x01
+
+#define WLED4_SINK_REG_STR_CABC(n) (0x56 + (n * 0x10))
+#define WLED4_SINK_REG_STR_CABC_MASK BIT(7)
+
+#define WLED4_SINK_REG_BRIGHT(n) (0x57 + (n * 0x10))
+
struct wled_var_cfg {
const u32 *values;
u32 (*fn)(u32);
@@ -90,6 +112,7 @@ struct wled {
struct device *dev;
struct regmap *regmap;
u16 ctrl_addr;
+ u16 sink_addr;
u16 max_string_count;
u32 brightness;
u32 max_brightness;
@@ -116,6 +139,29 @@ static int wled3_set_brightness(struct wled *wled, u16 brightness)
return 0;
}

+static int wled4_set_brightness(struct wled *wled, u16 brightness)
+{
+ int rc, i;
+ u16 low_limit = wled->max_brightness * 4 / 1000;
+ u8 v[2];
+
+ /* WLED4's lower limit of operation is 0.4% */
+ if (brightness > 0 && brightness < low_limit)
+ brightness = low_limit;
+
+ v[0] = brightness & 0xff;
+ v[1] = (brightness >> 8) & 0xf;
+
+ for (i = 0; i < wled->cfg.num_strings; ++i) {
+ rc = regmap_bulk_write(wled->regmap, wled->sink_addr +
+ WLED4_SINK_REG_BRIGHT(i), v, 2);
+ if (rc < 0)
+ return rc;
+ }
+
+ return 0;
+}
+
static int wled_module_enable(struct wled *wled, int val)
{
int rc;
@@ -267,6 +313,120 @@ static int wled3_setup(struct wled *wled)
.enabled_strings = {0, 1, 2, 3},
};

+static int wled4_setup(struct wled *wled)
+{
+ int rc, temp, i, j;
+ u16 addr;
+ u8 sink_en = 0;
+ u32 sink_cfg = 0;
+
+ rc = regmap_update_bits(wled->regmap,
+ wled->ctrl_addr + WLED3_CTRL_REG_OVP,
+ WLED3_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;
+
+ rc = regmap_read(wled->regmap, wled->sink_addr +
+ WLED4_SINK_REG_CURR_SINK, &sink_cfg);
+ if (rc < 0)
+ return rc;
+
+ for (i = 0; i < wled->cfg.num_strings; i++) {
+ j = wled->cfg.enabled_strings[i];
+ temp = j + WLED4_SINK_REG_CURR_SINK_SHFT;
+ sink_en |= 1 << temp;
+ }
+
+ if (sink_cfg == sink_en)
+ return 0;
+
+ rc = regmap_update_bits(wled->regmap,
+ wled->sink_addr + WLED4_SINK_REG_CURR_SINK,
+ WLED4_SINK_REG_CURR_SINK_MASK, 0);
+ if (rc < 0)
+ return rc;
+
+ rc = regmap_update_bits(wled->regmap, wled->ctrl_addr +
+ WLED3_CTRL_REG_MOD_EN,
+ WLED3_CTRL_REG_MOD_EN_MASK, 0);
+ 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_MOD_EN(j);
+ rc = regmap_update_bits(wled->regmap, addr,
+ WLED4_SINK_REG_STR_MOD_MASK,
+ WLED4_SINK_REG_STR_MOD_MASK);
+ if (rc < 0)
+ return rc;
+
+ 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 +
+ WLED4_SINK_REG_STR_CABC(j);
+ rc = regmap_update_bits(wled->regmap, addr,
+ WLED4_SINK_REG_STR_CABC_MASK,
+ wled->cfg.cabc ?
+ WLED4_SINK_REG_STR_CABC_MASK : 0);
+ if (rc < 0)
+ return rc;
+ }
+
+ rc = regmap_update_bits(wled->regmap, wled->ctrl_addr +
+ WLED3_CTRL_REG_MOD_EN,
+ WLED3_CTRL_REG_MOD_EN_MASK,
+ WLED3_CTRL_REG_MOD_EN_MASK);
+ 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;
+
+ rc = wled_sync_toggle(wled);
+ if (rc < 0) {
+ dev_err(wled->dev, "Failed to toggle sync reg rc:%d\n", rc);
+ return rc;
+ }
+
+ return 0;
+}
+
+static const struct wled_config wled4_config_defaults = {
+ .boost_i_limit = 4,
+ .string_i_limit = 10,
+ .ovp = 1,
+ .num_strings = 4,
+ .switch_freq = 11,
+ .cabc = false,
+};
+
static const u32 wled3_boost_i_limit_values[] = {
105, 385, 525, 805, 980, 1260, 1400, 1680,
};
@@ -276,6 +436,15 @@ static int wled3_setup(struct wled *wled)
.size = ARRAY_SIZE(wled3_boost_i_limit_values),
};

+static const u32 wled4_boost_i_limit_values[] = {
+ 105, 280, 450, 620, 970, 1150, 1300, 1500,
+};
+
+static const struct wled_var_cfg wled4_boost_i_limit_cfg = {
+ .values = wled4_boost_i_limit_values,
+ .size = ARRAY_SIZE(wled4_boost_i_limit_values),
+};
+
static const u32 wled3_ovp_values[] = {
35, 32, 29, 27,
};
@@ -285,6 +454,15 @@ static int wled3_setup(struct wled *wled)
.size = ARRAY_SIZE(wled3_ovp_values),
};

+static const u32 wled4_ovp_values[] = {
+ 31100, 29600, 19600, 18100,
+};
+
+static const struct wled_var_cfg wled4_ovp_cfg = {
+ .values = wled4_ovp_values,
+ .size = ARRAY_SIZE(wled4_ovp_values),
+};
+
static u32 wled3_num_strings_values_fn(u32 idx)
{
return idx + 1;
@@ -295,6 +473,11 @@ static u32 wled3_num_strings_values_fn(u32 idx)
.size = 3,
};

+static const struct wled_var_cfg wled4_num_strings_cfg = {
+ .fn = wled3_num_strings_values_fn,
+ .size = 4,
+};
+
static u32 wled3_switch_freq_values_fn(u32 idx)
{
return 19200 / (2 * (1 + idx));
@@ -309,10 +492,24 @@ static u32 wled3_switch_freq_values_fn(u32 idx)
.size = 26,
};

+static const u32 wled4_string_i_limit_values[] = {
+ 0, 2500, 5000, 7500, 10000, 12500, 15000, 17500, 20000,
+ 22500, 25000, 27500, 30000,
+};
+
+static const struct wled_var_cfg wled4_string_i_limit_cfg = {
+ .values = wled4_string_i_limit_values,
+ .size = ARRAY_SIZE(wled4_string_i_limit_values),
+};
+
static const struct wled_var_cfg wled3_string_cfg = {
.size = 8,
};

+static const struct wled_var_cfg wled4_string_cfg = {
+ .size = 16,
+};
+
static u32 wled_values(const struct wled_var_cfg *cfg, u32 idx)
{
if (idx >= cfg->size)
@@ -361,6 +558,34 @@ static int wled_configure(struct wled *wled, int version)
},
};

+ const struct wled_u32_opts wled4_opts[] = {
+ {
+ .name = "qcom,current-boost-limit",
+ .val_ptr = &cfg->boost_i_limit,
+ .cfg = &wled4_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 = &wled4_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,
+ },
+ };
+
const struct wled_bool_opts bool_opts[] = {
{ "qcom,cs-out", &cfg->cs_out_en, },
{ "qcom,ext-gen", &cfg->ext_gen, },
@@ -385,6 +610,22 @@ static int wled_configure(struct wled *wled, int version)
*cfg = wled3_config_defaults;
wled->wled_set_brightness = wled3_set_brightness;
wled->max_string_count = 3;
+ wled->sink_addr = wled->ctrl_addr;
+ break;
+
+ case 4:
+ u32_opts = wled4_opts;
+ size = ARRAY_SIZE(wled4_opts);
+ *cfg = wled4_config_defaults;
+ wled->wled_set_brightness = wled4_set_brightness;
+ 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:
@@ -483,6 +724,14 @@ static int wled_probe(struct platform_device *pdev)
}
break;

+ case 4:
+ rc = wled4_setup(wled);
+ if (rc) {
+ dev_err(&pdev->dev, "wled4_setup failed\n");
+ return rc;
+ }
+ break;
+
default:
dev_err(wled->dev, "Invalid WLED version\n");
break;
@@ -503,6 +752,8 @@ static int wled_probe(struct platform_device *pdev)

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 },
{}
};
MODULE_DEVICE_TABLE(of, wled_match_table);
--
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