Re: [PATCH V4 6/8] backlight: qcom-wled: Add support for WLED4 peripheral

From: Daniel Thompson
Date: Fri Jul 20 2018 - 09:47:35 EST

On 09/07/18 11:22, Kiran Gunda wrote:
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>
---
Changes from V3:
- The WLED3 specific changes are splitted out
- Merged the wled3_sync_toggle and wled4_syn_toggle functions
- Modified the compatible .data
- Moved from if/else to switch/case to select the version specific data
- Addressed few more minor comments from Bjorn

drivers/video/backlight/qcom-wled.c | 264 +++++++++++++++++++++++++++++++++++-
1 file changed, 258 insertions(+), 6 deletions(-)

diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index 87fc1d0..362d254 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c
@@ -64,6 +64,28 @@
#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);
@@ -98,6 +120,7 @@ struct wled {
struct device *dev;
struct regmap *regmap;
u16 ctrl_addr;
+ u16 sink_addr;
u16 max_string_count;
u32 brightness;
u32 max_brightness;
@@ -124,6 +147,29 @@ 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;
@@ -141,13 +187,13 @@ static int wled_sync_toggle(struct wled *wled)
unsigned int mask = GENMASK(wled->max_string_count - 1, 0);
rc = regmap_update_bits(wled->regmap,
- wled->ctrl_addr + WLED_SINK_REG_SYNC,
+ wled->sink_addr + WLED_SINK_REG_SYNC,
mask, mask);
if (rc < 0)
return rc;
rc = regmap_update_bits(wled->regmap,
- wled->ctrl_addr + WLED_SINK_REG_SYNC,
+ wled->sink_addr + WLED_SINK_REG_SYNC,
mask, WLED_SINK_REG_SYNC_CLEAR);
return rc;
@@ -274,6 +320,120 @@ static int wled3_setup(struct wled *wled)
.cabc = false,
};
+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 + WLED_CTRL_REG_OVP,
+ WLED_CTRL_REG_OVP_MASK, wled->cfg.ovp);
+ if (rc < 0)
+ return rc;
+
+ rc = regmap_update_bits(wled->regmap,
+ wled->ctrl_addr + WLED_CTRL_REG_ILIMIT,
+ WLED_CTRL_REG_ILIMIT_MASK,
+ wled->cfg.boost_i_limit);
+ if (rc < 0)
+ return rc;
+
+ rc = regmap_update_bits(wled->regmap,
+ wled->ctrl_addr + WLED_CTRL_REG_FREQ,
+ WLED_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 +
+ WLED_CTRL_REG_MOD_EN,
+ WLED_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 +
+ WLED_CTRL_REG_MOD_EN,
+ WLED_CTRL_REG_MOD_EN_MASK,
+ WLED_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,
};
@@ -283,6 +443,15 @@ 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,
};
@@ -292,6 +461,15 @@ 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;
@@ -302,6 +480,11 @@ 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));
@@ -316,10 +499,24 @@ 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)
@@ -332,6 +529,7 @@ static u32 wled_values(const struct wled_var_cfg *cfg, u32 idx)
}
#define WLED3 3
+#define WLED4 4

Are these macros always going to define 3 to be 3 and 4 to be 4. If so we probably don't need them (and they should be removed from patch 5/8 too).

There is a degree of nitpicking here however. The rest looks OK to me.


Daniel.