From: Courtney Cavin <[email protected]>
This adds device tree binding documentation for the WLED ('White' LED)
block on Qualcomm's PM8941 PMICs.
Signed-off-by: Courtney Cavin <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>
---
.../devicetree/bindings/leds/leds-pm8941-wled.txt | 43 ++++++++++++++++++++++
1 file changed, 43 insertions(+)
create mode 100644 Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt
diff --git a/Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt b/Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt
new file mode 100644
index 0000000..a85a964
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt
@@ -0,0 +1,43 @@
+Binding for Qualcomm PM8941 WLED driver
+
+Required properties:
+- compatible: should be "qcom,pm8941-wled"
+- reg: slave address
+
+Optional properties:
+- label: The label for this led
+ See Documentation/devicetree/bindings/leds/common.txt
+- linux,default-trigger: Default trigger assigned to the LED
+ See Documentation/devicetree/bindings/leds/common.txt
+- qcom,cs-out: bool; enable current sink output
+- qcom,cabc: bool; enable content adaptive backlight control
+- qcom,ext-gen: bool; use externally generated modulator signal to dim
+- qcom,current-limit: mA; per-string current limit; value from 0 to 25
+ default: 20mA
+- qcom,current-boost-limit: mA; boost current limit; one of:
+ 105, 385, 525, 805, 980, 1260, 1400, 1680
+ default: 805mA
+- qcom,switching-freq: kHz; switching frequency; one of:
+ 600, 640, 685, 738, 800, 872, 960, 1066, 1200, 1371,
+ 1600, 1920, 2400, 3200, 4800, 9600,
+ default: 1600kHz
+- qcom,ovp: V; Over-voltage protection limit; one of:
+ 27, 29, 32, 35
+ default: 29V
+- qcom,num-strings: #; number of led strings attached; value from 1 to 3
+ default: 2
+
+Example:
+
+pm8941-wled@d800 {
+ compatible = "qcom,pm8941-wled";
+ reg = <0xd800>;
+ label = "backlight";
+
+ qcom,cs-out;
+ qcom,current-limit = <20>;
+ qcom,current-boost-limit = <805>;
+ qcom,switching-freq = <1600>;
+ qcom,ovp = <29>;
+ qcom,num-strings = <2>;
+};
--
1.8.2.2
From: Courtney Cavin <[email protected]>
This adds support for the WLED ('White' LED) block on Qualcomm's
PM8941 PMICs.
Signed-off-by: Courtney Cavin <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>
---
drivers/leds/Kconfig | 8 +
drivers/leds/Makefile | 1 +
drivers/leds/leds-pm8941-wled.c | 466 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 475 insertions(+)
create mode 100644 drivers/leds/leds-pm8941-wled.c
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index a210338..9091cf4 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -505,6 +505,14 @@ config LEDS_VERSATILE
This option enabled support for the LEDs on the ARM Versatile
and RealView boards. Say Y to enabled these.
+config LEDS_PM8941_WLED
+ tristate "LED support for the Qualcomm PM8941 WLED block"
+ depends on LEDS_CLASS
+ depends on REGMAP
+ help
+ This option enables support for the 'White' LED block
+ on Qualcomm PM8941 PMICs.
+
comment "LED Triggers"
source "drivers/leds/trigger/Kconfig"
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index a2b1647..5474afc 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -56,6 +56,7 @@ obj-$(CONFIG_LEDS_BLINKM) += leds-blinkm.o
obj-$(CONFIG_LEDS_SYSCON) += leds-syscon.o
obj-$(CONFIG_LEDS_VERSATILE) += leds-versatile.o
obj-$(CONFIG_LEDS_MENF21BMC) += leds-menf21bmc.o
+obj-$(CONFIG_LEDS_PM8941_WLED) += leds-pm8941-wled.o
# LED SPI Drivers
obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o
diff --git a/drivers/leds/leds-pm8941-wled.c b/drivers/leds/leds-pm8941-wled.c
new file mode 100644
index 0000000..aa06d0b
--- /dev/null
+++ b/drivers/leds/leds-pm8941-wled.c
@@ -0,0 +1,466 @@
+/* Copyright (c) 2013, Sony Mobile Communications, AB.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+
+enum pm8941_wled_reg {
+ PM8941_WLED_REG_VAL_BASE = 0x40,
+#define PM8941_WLED_REG_VAL_MAX 0xFFF
+
+ PM8941_WLED_REG_MOD_EN = 0x46,
+#define PM8941_WLED_REG_MOD_EN_BIT BIT(7)
+#define PM8941_WLED_REG_MOD_EN_MASK BIT(7)
+
+ PM8941_WLED_REG_SYNC = 0x47,
+#define PM8941_WLED_REG_SYNC_MASK 0x07
+#define PM8941_WLED_REG_SYNC_LED1 BIT(0)
+#define PM8941_WLED_REG_SYNC_LED2 BIT(1)
+#define PM8941_WLED_REG_SYNC_LED3 BIT(2)
+#define PM8941_WLED_REG_SYNC_ALL 0x07
+#define PM8941_WLED_REG_SYNC_CLEAR 0x00
+
+ PM8941_WLED_REG_FREQ = 0x4c,
+#define PM8941_WLED_REG_FREQ_MASK 0x0f
+
+ PM8941_WLED_REG_OVP = 0x4d,
+#define PM8941_WLED_REG_OVP_MASK 0x03
+
+ PM8941_WLED_REG_BOOST = 0x4e,
+#define PM8941_WLED_REG_BOOST_MASK 0x07
+
+ PM8941_WLED_REG_SINK = 0x4f,
+#define PM8941_WLED_REG_SINK_MASK 0xe0
+#define PM8941_WLED_REG_SINK_SHFT 0x05
+
+/* Per-'string' registers below */
+#define PM8941_WLED_REG_STR_OFFSET 0x10
+
+ PM8941_WLED_REG_STR_MOD_EN_BASE = 0x60,
+#define PM8941_WLED_REG_STR_MOD_EN BIT(7)
+#define PM8941_WLED_REG_STR_MOD_MASK BIT(7)
+
+ PM8941_WLED_REG_STR_SCALE_BASE = 0x62,
+#define PM8941_WLED_REG_STR_SCALE_MASK 0x1f
+
+ PM8941_WLED_REG_STR_MOD_SRC_BASE = 0x63,
+#define PM8941_WLED_REG_STR_MOD_SRC_MASK 0x01
+#define PM8941_WLED_REG_STR_MOD_SRC_INT 0x00
+#define PM8941_WLED_REG_STR_MOD_SRC_EXT 0x01
+
+ PM8941_WLED_REG_STR_CABC_BASE = 0x66,
+#define PM8941_WLED_REG_STR_CABC_MASK BIT(7)
+#define PM8941_WLED_REG_STR_CABC_EN BIT(7)
+};
+
+struct pm8941_wled_config {
+ u32 i_boost_limit;
+ u32 ovp;
+ u32 switch_freq;
+ u32 num_strings;
+ u32 i_limit;
+ bool cs_out_en;
+ bool ext_gen;
+ bool cabc_en;
+};
+
+struct pm8941_wled {
+ struct led_classdev cdev;
+ struct pm8941_wled_config cfg;
+ u16 addr;
+};
+
+struct pm8941_wled_context {
+ struct pm8941_wled wled;
+ struct regmap *regmap;
+};
+
+static int pm8941_wled_set(struct led_classdev *cdev,
+ enum led_brightness value)
+{
+ struct pm8941_wled_context *ctx;
+ struct pm8941_wled *wled;
+ u8 ctrl = 0;
+ u16 val;
+ int rc;
+ int i;
+
+ wled = container_of(cdev, struct pm8941_wled, cdev);
+ ctx = container_of(wled, struct pm8941_wled_context, wled);
+
+ if (value != 0)
+ ctrl = PM8941_WLED_REG_MOD_EN_BIT;
+
+ val = (value * PM8941_WLED_REG_VAL_MAX) / LED_FULL;
+
+ rc = regmap_update_bits(ctx->regmap,
+ wled->addr + PM8941_WLED_REG_MOD_EN,
+ PM8941_WLED_REG_MOD_EN_MASK, ctrl);
+ if (rc)
+ return rc;
+
+ for (i = 0; i < wled->cfg.num_strings; ++i) {
+ u8 v[2] = { val & 0xff, (val >> 8) & 0xf };
+
+ rc = regmap_bulk_write(ctx->regmap,
+ wled->addr + PM8941_WLED_REG_VAL_BASE + 2 * i,
+ v, 2);
+ if (rc)
+ return rc;
+ }
+
+ rc = regmap_update_bits(ctx->regmap,
+ wled->addr + PM8941_WLED_REG_SYNC,
+ PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_ALL);
+ if (rc)
+ return rc;
+
+ rc = regmap_update_bits(ctx->regmap,
+ wled->addr + PM8941_WLED_REG_SYNC,
+ PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_CLEAR);
+ return rc;
+}
+
+static void pm8941_wled_set_brightness(struct led_classdev *cdev,
+ enum led_brightness value)
+{
+ if (pm8941_wled_set(cdev, value)) {
+ dev_err(cdev->dev, "Unable to set brightness\n");
+ return;
+ }
+ cdev->brightness = value;
+}
+
+static int pm8941_wled_setup(struct pm8941_wled *wled)
+{
+ struct pm8941_wled_context *ctx;
+ int rc;
+ int i;
+
+ ctx = container_of(wled, struct pm8941_wled_context, wled);
+ rc = regmap_update_bits(ctx->regmap,
+ wled->addr + PM8941_WLED_REG_OVP,
+ PM8941_WLED_REG_OVP_MASK, wled->cfg.ovp);
+ if (rc)
+ return rc;
+
+ rc = regmap_update_bits(ctx->regmap,
+ wled->addr + PM8941_WLED_REG_BOOST,
+ PM8941_WLED_REG_BOOST_MASK, wled->cfg.i_boost_limit);
+ if (rc)
+ return rc;
+
+ rc = regmap_update_bits(ctx->regmap,
+ wled->addr + PM8941_WLED_REG_FREQ,
+ PM8941_WLED_REG_FREQ_MASK, wled->cfg.switch_freq);
+ if (rc)
+ return rc;
+
+ if (wled->cfg.cs_out_en) {
+ u8 all = (BIT(wled->cfg.num_strings) - 1)
+ << PM8941_WLED_REG_SINK_SHFT;
+
+ rc = regmap_update_bits(ctx->regmap,
+ wled->addr + PM8941_WLED_REG_SINK,
+ PM8941_WLED_REG_SINK_MASK, all);
+ if (rc)
+ return rc;
+ }
+
+ for (i = 0; i < wled->cfg.num_strings; ++i) {
+ u16 addr = wled->addr + PM8941_WLED_REG_STR_OFFSET * i;
+
+ rc = regmap_update_bits(ctx->regmap,
+ addr + PM8941_WLED_REG_STR_MOD_EN_BASE,
+ PM8941_WLED_REG_STR_MOD_MASK,
+ PM8941_WLED_REG_STR_MOD_EN);
+ if (rc)
+ return rc;
+
+ if (wled->cfg.ext_gen) {
+ rc = regmap_update_bits(ctx->regmap,
+ addr + PM8941_WLED_REG_STR_MOD_SRC_BASE,
+ PM8941_WLED_REG_STR_MOD_SRC_MASK,
+ PM8941_WLED_REG_STR_MOD_SRC_EXT);
+ if (rc)
+ return rc;
+ }
+
+ rc = regmap_update_bits(ctx->regmap,
+ addr + PM8941_WLED_REG_STR_SCALE_BASE,
+ PM8941_WLED_REG_STR_SCALE_MASK,
+ wled->cfg.i_limit);
+ if (rc)
+ return rc;
+
+ rc = regmap_update_bits(ctx->regmap,
+ addr + PM8941_WLED_REG_STR_CABC_BASE,
+ PM8941_WLED_REG_STR_CABC_MASK,
+ wled->cfg.cabc_en ?
+ PM8941_WLED_REG_STR_CABC_EN : 0);
+ if (rc)
+ return rc;
+ }
+
+ return 0;
+}
+
+static const struct pm8941_wled_config pm8941_wled_config_defaults = {
+ .i_boost_limit = 3,
+ .i_limit = 20,
+ .ovp = 2,
+ .switch_freq = 5,
+ .num_strings = 0,
+ .cs_out_en = false,
+ .ext_gen = false,
+ .cabc_en = false,
+};
+
+struct pm8941_wled_var_cfg {
+ const u32 *values;
+ u32 (*fn)(u32);
+ int size;
+};
+
+static const u32 pm8941_wled_i_boost_limit_values[] = {
+ 105, 385, 525, 805, 980, 1260, 1400, 1680,
+};
+
+static const struct pm8941_wled_var_cfg pm8941_wled_i_boost_limit_cfg = {
+ .values = pm8941_wled_i_boost_limit_values,
+ .size = ARRAY_SIZE(pm8941_wled_i_boost_limit_values),
+};
+
+static const u32 pm8941_wled_ovp_values[] = {
+ 35, 32, 29, 27,
+};
+
+static const struct pm8941_wled_var_cfg pm8941_wled_ovp_cfg = {
+ .values = pm8941_wled_ovp_values,
+ .size = ARRAY_SIZE(pm8941_wled_ovp_values),
+};
+
+static u32 pm8941_wled_num_strings_values_fn(u32 idx)
+{
+ return idx + 1;
+}
+
+static const struct pm8941_wled_var_cfg pm8941_wled_num_strings_cfg = {
+ .fn = pm8941_wled_num_strings_values_fn,
+ .size = 3,
+};
+
+static u32 pm8941_wled_switch_freq_values_fn(u32 idx)
+{
+ return 19200 / (2 * (1 + idx));
+}
+
+static const struct pm8941_wled_var_cfg pm8941_wled_switch_freq_cfg = {
+ .fn = pm8941_wled_switch_freq_values_fn,
+ .size = 16,
+};
+
+static const struct pm8941_wled_var_cfg pm8941_wled_i_limit_cfg = {
+ .size = 26,
+};
+
+static u32 pm8941_wled_values(const struct pm8941_wled_var_cfg *cfg, u32 idx)
+{
+ if (idx >= cfg->size)
+ return UINT_MAX;
+ if (cfg->fn)
+ return cfg->fn(idx);
+ if (cfg->values)
+ return cfg->values[idx];
+ return idx;
+}
+
+static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
+{
+ struct pm8941_wled_config *cfg = &wled->cfg;
+ u32 val;
+ int rc;
+ int i;
+
+ const struct {
+ const char *name;
+ u32 *val_ptr;
+ const struct pm8941_wled_var_cfg *cfg;
+ } u32_opts[] = {
+ {
+ "qcom,current-boost-limit", &cfg->i_boost_limit,
+ .cfg = &pm8941_wled_i_boost_limit_cfg,
+ },
+ {
+ "qcom,current-limit", &cfg->i_limit,
+ .cfg = &pm8941_wled_i_limit_cfg,
+ },
+ {
+ "qcom,ovp", &cfg->ovp,
+ .cfg = &pm8941_wled_ovp_cfg,
+ },
+ {
+ "qcom,switching-freq", &cfg->switch_freq,
+ .cfg = &pm8941_wled_switch_freq_cfg,
+ },
+ {
+ "qcom,num-strings", &cfg->num_strings,
+ .cfg = &pm8941_wled_num_strings_cfg,
+ },
+ };
+ const struct {
+ const char *name;
+ bool *val_ptr;
+ } bool_opts[] = {
+ { "qcom,cs-out", &cfg->cs_out_en, },
+ { "qcom,ext-gen", &cfg->ext_gen, },
+ { "qcom,cabc", &cfg->cabc_en, },
+ };
+
+ if (dev->of_node == NULL) {
+ dev_err(dev, "no OF node!\n");
+ return -EINVAL;
+ }
+
+ rc = of_property_read_u32(dev->of_node, "reg", &val);
+ if (rc || val > 0xffff) {
+ dev_err(dev, "invalid IO resources\n");
+ return rc ? rc : -EINVAL;
+ }
+ wled->addr = val;
+
+ rc = of_property_read_string(dev->of_node, "label", &wled->cdev.name);
+ if (rc)
+ wled->cdev.name = dev->of_node->name;
+
+ wled->cdev.default_trigger = of_get_property(dev->of_node,
+ "linux,default-trigger", NULL);
+
+ *cfg = pm8941_wled_config_defaults;
+ for (i = 0; i < ARRAY_SIZE(u32_opts); ++i) {
+ u32 sel, c;
+ int j, rj;
+
+ rc = of_property_read_u32(dev->of_node, u32_opts[i].name, &val);
+ if (rc) {
+ if (rc != -EINVAL) {
+ dev_err(dev, "error reading '%s'\n",
+ u32_opts[i].name);
+ return rc;
+ }
+ continue;
+ }
+
+ sel = UINT_MAX;
+ rj = -1;
+ c = pm8941_wled_values(u32_opts[i].cfg, 0);
+ for (j = 0; c != UINT_MAX; ++j) {
+ if (c <= val && (sel == UINT_MAX || c >= sel)) {
+ sel = c;
+ rj = j;
+ }
+ c = pm8941_wled_values(u32_opts[i].cfg, j + 1);
+ }
+ if (sel == UINT_MAX) {
+ dev_err(dev, "invalid value for '%s'\n",
+ u32_opts[i].name);
+ return rc;
+ }
+ if (sel != val) {
+ dev_warn(dev, "rounding '%s' down to %u\n",
+ u32_opts[i].name, sel);
+ }
+ dev_dbg(dev, "'%s' = %u\n", u32_opts[i].name, sel);
+ *u32_opts[i].val_ptr = rj;
+ };
+
+ for (i = 0; i < ARRAY_SIZE(bool_opts); ++i) {
+ if (of_property_read_bool(dev->of_node, bool_opts[i].name))
+ *bool_opts[i].val_ptr = true;
+ }
+
+ cfg->num_strings = cfg->num_strings + 1;
+
+ return 0;
+}
+
+static int pm8941_wled_probe(struct platform_device *pdev)
+{
+ struct pm8941_wled_context *ctx;
+ struct regmap *regmap;
+ int rc;
+
+ regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!regmap) {
+ dev_err(&pdev->dev, "Unable to get regmap\n");
+ return -EINVAL;
+ }
+
+ ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
+ if (ctx == NULL)
+ return -ENOMEM;
+
+ ctx->regmap = regmap;
+
+ rc = pm8941_wled_configure(&ctx->wled, &pdev->dev);
+ if (rc)
+ return rc;
+
+ rc = pm8941_wled_setup(&ctx->wled);
+ if (rc)
+ return rc;
+
+ ctx->wled.cdev.brightness_set = pm8941_wled_set_brightness;
+
+ rc = led_classdev_register(&pdev->dev, &ctx->wled.cdev);
+ if (rc)
+ return rc;
+
+ platform_set_drvdata(pdev, ctx);
+ dev_info(&pdev->dev, "registered led \"%s\"\n", ctx->wled.cdev.name);
+
+ return 0;
+};
+
+static int pm8941_wled_remove(struct platform_device *pdev)
+{
+ struct pm8941_wled_context *ctx;
+
+ ctx = platform_get_drvdata(pdev);
+ led_classdev_unregister(&ctx->wled.cdev);
+
+ return 0;
+}
+
+static const struct of_device_id pm8941_wled_match_table[] = {
+ { .compatible = "qcom,pm8941-wled" },
+ {}
+};
+
+static struct platform_driver pm8941_wled_driver = {
+ .probe = pm8941_wled_probe,
+ .remove = pm8941_wled_remove,
+ .driver = {
+ .name = "pm8941-wled",
+ .owner = THIS_MODULE,
+ .of_match_table = pm8941_wled_match_table,
+ },
+};
+
+module_platform_driver(pm8941_wled_driver);
+
+MODULE_DESCRIPTION("pm8941 wled driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform: pm8941-wled");
--
1.8.2.2
On Mon, Dec 8, 2014 at 4:22 PM, Bjorn Andersson
<[email protected]> wrote:
> From: Courtney Cavin <[email protected]>
>
> This adds device tree binding documentation for the WLED ('White' LED)
> block on Qualcomm's PM8941 PMICs.
>
Looks good to me, I need device tree reviewer's Ack to merge it.
Thanks,
-Bryan
> Signed-off-by: Courtney Cavin <[email protected]>
> Signed-off-by: Bjorn Andersson <[email protected]>
> ---
> .../devicetree/bindings/leds/leds-pm8941-wled.txt | 43 ++++++++++++++++++++++
> 1 file changed, 43 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt
>
> diff --git a/Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt b/Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt
> new file mode 100644
> index 0000000..a85a964
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt
> @@ -0,0 +1,43 @@
> +Binding for Qualcomm PM8941 WLED driver
> +
> +Required properties:
> +- compatible: should be "qcom,pm8941-wled"
> +- reg: slave address
> +
> +Optional properties:
> +- label: The label for this led
> + See Documentation/devicetree/bindings/leds/common.txt
> +- linux,default-trigger: Default trigger assigned to the LED
> + See Documentation/devicetree/bindings/leds/common.txt
> +- qcom,cs-out: bool; enable current sink output
> +- qcom,cabc: bool; enable content adaptive backlight control
> +- qcom,ext-gen: bool; use externally generated modulator signal to dim
> +- qcom,current-limit: mA; per-string current limit; value from 0 to 25
> + default: 20mA
> +- qcom,current-boost-limit: mA; boost current limit; one of:
> + 105, 385, 525, 805, 980, 1260, 1400, 1680
> + default: 805mA
> +- qcom,switching-freq: kHz; switching frequency; one of:
> + 600, 640, 685, 738, 800, 872, 960, 1066, 1200, 1371,
> + 1600, 1920, 2400, 3200, 4800, 9600,
> + default: 1600kHz
> +- qcom,ovp: V; Over-voltage protection limit; one of:
> + 27, 29, 32, 35
> + default: 29V
> +- qcom,num-strings: #; number of led strings attached; value from 1 to 3
> + default: 2
> +
> +Example:
> +
> +pm8941-wled@d800 {
> + compatible = "qcom,pm8941-wled";
> + reg = <0xd800>;
> + label = "backlight";
> +
> + qcom,cs-out;
> + qcom,current-limit = <20>;
> + qcom,current-boost-limit = <805>;
> + qcom,switching-freq = <1600>;
> + qcom,ovp = <29>;
> + qcom,num-strings = <2>;
> +};
> --
> 1.8.2.2
>
On Mon, Dec 8, 2014 at 4:22 PM, Bjorn Andersson
<[email protected]> wrote:
> From: Courtney Cavin <[email protected]>
>
> This adds support for the WLED ('White' LED) block on Qualcomm's
> PM8941 PMICs.
>
> Signed-off-by: Courtney Cavin <[email protected]>
> Signed-off-by: Bjorn Andersson <[email protected]>
> ---
> drivers/leds/Kconfig | 8 +
> drivers/leds/Makefile | 1 +
> drivers/leds/leds-pm8941-wled.c | 466 ++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 475 insertions(+)
> create mode 100644 drivers/leds/leds-pm8941-wled.c
>
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index a210338..9091cf4 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -505,6 +505,14 @@ config LEDS_VERSATILE
> This option enabled support for the LEDs on the ARM Versatile
> and RealView boards. Say Y to enabled these.
>
> +config LEDS_PM8941_WLED
> + tristate "LED support for the Qualcomm PM8941 WLED block"
> + depends on LEDS_CLASS
> + depends on REGMAP
Here should be "select REGMAP"
> + help
> + This option enables support for the 'White' LED block
> + on Qualcomm PM8941 PMICs.
> +
> comment "LED Triggers"
> source "drivers/leds/trigger/Kconfig"
>
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index a2b1647..5474afc 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -56,6 +56,7 @@ obj-$(CONFIG_LEDS_BLINKM) += leds-blinkm.o
> obj-$(CONFIG_LEDS_SYSCON) += leds-syscon.o
> obj-$(CONFIG_LEDS_VERSATILE) += leds-versatile.o
> obj-$(CONFIG_LEDS_MENF21BMC) += leds-menf21bmc.o
> +obj-$(CONFIG_LEDS_PM8941_WLED) += leds-pm8941-wled.o
>
> # LED SPI Drivers
> obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o
> diff --git a/drivers/leds/leds-pm8941-wled.c b/drivers/leds/leds-pm8941-wled.c
> new file mode 100644
> index 0000000..aa06d0b
> --- /dev/null
> +++ b/drivers/leds/leds-pm8941-wled.c
> @@ -0,0 +1,466 @@
> +/* Copyright (c) 2013, Sony Mobile Communications, AB.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/leds.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/regmap.h>
> +
> +enum pm8941_wled_reg {
> + PM8941_WLED_REG_VAL_BASE = 0x40,
> +#define PM8941_WLED_REG_VAL_MAX 0xFFF
> +
> + PM8941_WLED_REG_MOD_EN = 0x46,
> +#define PM8941_WLED_REG_MOD_EN_BIT BIT(7)
> +#define PM8941_WLED_REG_MOD_EN_MASK BIT(7)
> +
> + PM8941_WLED_REG_SYNC = 0x47,
> +#define PM8941_WLED_REG_SYNC_MASK 0x07
> +#define PM8941_WLED_REG_SYNC_LED1 BIT(0)
> +#define PM8941_WLED_REG_SYNC_LED2 BIT(1)
> +#define PM8941_WLED_REG_SYNC_LED3 BIT(2)
> +#define PM8941_WLED_REG_SYNC_ALL 0x07
> +#define PM8941_WLED_REG_SYNC_CLEAR 0x00
> +
> + PM8941_WLED_REG_FREQ = 0x4c,
> +#define PM8941_WLED_REG_FREQ_MASK 0x0f
> +
> + PM8941_WLED_REG_OVP = 0x4d,
> +#define PM8941_WLED_REG_OVP_MASK 0x03
> +
> + PM8941_WLED_REG_BOOST = 0x4e,
> +#define PM8941_WLED_REG_BOOST_MASK 0x07
> +
> + PM8941_WLED_REG_SINK = 0x4f,
> +#define PM8941_WLED_REG_SINK_MASK 0xe0
> +#define PM8941_WLED_REG_SINK_SHFT 0x05
> +
> +/* Per-'string' registers below */
> +#define PM8941_WLED_REG_STR_OFFSET 0x10
> +
> + PM8941_WLED_REG_STR_MOD_EN_BASE = 0x60,
> +#define PM8941_WLED_REG_STR_MOD_EN BIT(7)
> +#define PM8941_WLED_REG_STR_MOD_MASK BIT(7)
> +
> + PM8941_WLED_REG_STR_SCALE_BASE = 0x62,
> +#define PM8941_WLED_REG_STR_SCALE_MASK 0x1f
> +
> + PM8941_WLED_REG_STR_MOD_SRC_BASE = 0x63,
> +#define PM8941_WLED_REG_STR_MOD_SRC_MASK 0x01
> +#define PM8941_WLED_REG_STR_MOD_SRC_INT 0x00
> +#define PM8941_WLED_REG_STR_MOD_SRC_EXT 0x01
> +
> + PM8941_WLED_REG_STR_CABC_BASE = 0x66,
> +#define PM8941_WLED_REG_STR_CABC_MASK BIT(7)
> +#define PM8941_WLED_REG_STR_CABC_EN BIT(7)
> +};
> +
> +struct pm8941_wled_config {
> + u32 i_boost_limit;
> + u32 ovp;
> + u32 switch_freq;
> + u32 num_strings;
> + u32 i_limit;
> + bool cs_out_en;
> + bool ext_gen;
> + bool cabc_en;
> +};
> +
> +struct pm8941_wled {
> + struct led_classdev cdev;
> + struct pm8941_wled_config cfg;
> + u16 addr;
> +};
> +
> +struct pm8941_wled_context {
> + struct pm8941_wled wled;
> + struct regmap *regmap;
> +};
> +
I think you can just add *regmap into pm8941_wled struct and
pm8941_wled_context is redundant to me.
> +static int pm8941_wled_set(struct led_classdev *cdev,
> + enum led_brightness value)
> +{
> + struct pm8941_wled_context *ctx;
> + struct pm8941_wled *wled;
> + u8 ctrl = 0;
> + u16 val;
> + int rc;
> + int i;
> +
> + wled = container_of(cdev, struct pm8941_wled, cdev);
> + ctx = container_of(wled, struct pm8941_wled_context, wled);
> +
> + if (value != 0)
> + ctrl = PM8941_WLED_REG_MOD_EN_BIT;
> +
> + val = (value * PM8941_WLED_REG_VAL_MAX) / LED_FULL;
> +
> + rc = regmap_update_bits(ctx->regmap,
> + wled->addr + PM8941_WLED_REG_MOD_EN,
> + PM8941_WLED_REG_MOD_EN_MASK, ctrl);
> + if (rc)
> + return rc;
> +
> + for (i = 0; i < wled->cfg.num_strings; ++i) {
> + u8 v[2] = { val & 0xff, (val >> 8) & 0xf };
> +
> + rc = regmap_bulk_write(ctx->regmap,
> + wled->addr + PM8941_WLED_REG_VAL_BASE + 2 * i,
> + v, 2);
> + if (rc)
> + return rc;
> + }
> +
> + rc = regmap_update_bits(ctx->regmap,
> + wled->addr + PM8941_WLED_REG_SYNC,
> + PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_ALL);
> + if (rc)
> + return rc;
> +
> + rc = regmap_update_bits(ctx->regmap,
> + wled->addr + PM8941_WLED_REG_SYNC,
> + PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_CLEAR);
> + return rc;
> +}
> +
> +static void pm8941_wled_set_brightness(struct led_classdev *cdev,
> + enum led_brightness value)
> +{
> + if (pm8941_wled_set(cdev, value)) {
> + dev_err(cdev->dev, "Unable to set brightness\n");
> + return;
> + }
> + cdev->brightness = value;
> +}
> +
> +static int pm8941_wled_setup(struct pm8941_wled *wled)
> +{
> + struct pm8941_wled_context *ctx;
> + int rc;
> + int i;
> +
> + ctx = container_of(wled, struct pm8941_wled_context, wled);
> + rc = regmap_update_bits(ctx->regmap,
> + wled->addr + PM8941_WLED_REG_OVP,
> + PM8941_WLED_REG_OVP_MASK, wled->cfg.ovp);
> + if (rc)
> + return rc;
> +
> + rc = regmap_update_bits(ctx->regmap,
> + wled->addr + PM8941_WLED_REG_BOOST,
> + PM8941_WLED_REG_BOOST_MASK, wled->cfg.i_boost_limit);
> + if (rc)
> + return rc;
> +
> + rc = regmap_update_bits(ctx->regmap,
> + wled->addr + PM8941_WLED_REG_FREQ,
> + PM8941_WLED_REG_FREQ_MASK, wled->cfg.switch_freq);
> + if (rc)
> + return rc;
> +
> + if (wled->cfg.cs_out_en) {
> + u8 all = (BIT(wled->cfg.num_strings) - 1)
> + << PM8941_WLED_REG_SINK_SHFT;
> +
> + rc = regmap_update_bits(ctx->regmap,
> + wled->addr + PM8941_WLED_REG_SINK,
> + PM8941_WLED_REG_SINK_MASK, all);
> + if (rc)
> + return rc;
> + }
> +
> + for (i = 0; i < wled->cfg.num_strings; ++i) {
> + u16 addr = wled->addr + PM8941_WLED_REG_STR_OFFSET * i;
> +
> + rc = regmap_update_bits(ctx->regmap,
> + addr + PM8941_WLED_REG_STR_MOD_EN_BASE,
> + PM8941_WLED_REG_STR_MOD_MASK,
> + PM8941_WLED_REG_STR_MOD_EN);
> + if (rc)
> + return rc;
> +
> + if (wled->cfg.ext_gen) {
> + rc = regmap_update_bits(ctx->regmap,
> + addr + PM8941_WLED_REG_STR_MOD_SRC_BASE,
> + PM8941_WLED_REG_STR_MOD_SRC_MASK,
> + PM8941_WLED_REG_STR_MOD_SRC_EXT);
> + if (rc)
> + return rc;
> + }
> +
> + rc = regmap_update_bits(ctx->regmap,
> + addr + PM8941_WLED_REG_STR_SCALE_BASE,
> + PM8941_WLED_REG_STR_SCALE_MASK,
> + wled->cfg.i_limit);
> + if (rc)
> + return rc;
> +
> + rc = regmap_update_bits(ctx->regmap,
> + addr + PM8941_WLED_REG_STR_CABC_BASE,
> + PM8941_WLED_REG_STR_CABC_MASK,
> + wled->cfg.cabc_en ?
> + PM8941_WLED_REG_STR_CABC_EN : 0);
> + if (rc)
> + return rc;
> + }
> +
> + return 0;
> +}
> +
> +static const struct pm8941_wled_config pm8941_wled_config_defaults = {
> + .i_boost_limit = 3,
> + .i_limit = 20,
> + .ovp = 2,
> + .switch_freq = 5,
> + .num_strings = 0,
> + .cs_out_en = false,
> + .ext_gen = false,
> + .cabc_en = false,
> +};
> +
> +struct pm8941_wled_var_cfg {
> + const u32 *values;
> + u32 (*fn)(u32);
> + int size;
> +};
> +
> +static const u32 pm8941_wled_i_boost_limit_values[] = {
> + 105, 385, 525, 805, 980, 1260, 1400, 1680,
> +};
> +
> +static const struct pm8941_wled_var_cfg pm8941_wled_i_boost_limit_cfg = {
> + .values = pm8941_wled_i_boost_limit_values,
> + .size = ARRAY_SIZE(pm8941_wled_i_boost_limit_values),
> +};
> +
> +static const u32 pm8941_wled_ovp_values[] = {
> + 35, 32, 29, 27,
> +};
> +
> +static const struct pm8941_wled_var_cfg pm8941_wled_ovp_cfg = {
> + .values = pm8941_wled_ovp_values,
> + .size = ARRAY_SIZE(pm8941_wled_ovp_values),
> +};
> +
> +static u32 pm8941_wled_num_strings_values_fn(u32 idx)
> +{
> + return idx + 1;
> +}
> +
> +static const struct pm8941_wled_var_cfg pm8941_wled_num_strings_cfg = {
> + .fn = pm8941_wled_num_strings_values_fn,
> + .size = 3,
> +};
> +
> +static u32 pm8941_wled_switch_freq_values_fn(u32 idx)
> +{
> + return 19200 / (2 * (1 + idx));
> +}
> +
> +static const struct pm8941_wled_var_cfg pm8941_wled_switch_freq_cfg = {
> + .fn = pm8941_wled_switch_freq_values_fn,
> + .size = 16,
> +};
> +
> +static const struct pm8941_wled_var_cfg pm8941_wled_i_limit_cfg = {
> + .size = 26,
> +};
> +
> +static u32 pm8941_wled_values(const struct pm8941_wled_var_cfg *cfg, u32 idx)
> +{
> + if (idx >= cfg->size)
> + return UINT_MAX;
> + if (cfg->fn)
> + return cfg->fn(idx);
> + if (cfg->values)
> + return cfg->values[idx];
> + return idx;
> +}
> +
> +static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
> +{
> + struct pm8941_wled_config *cfg = &wled->cfg;
> + u32 val;
> + int rc;
> + int i;
> +
> + const struct {
> + const char *name;
> + u32 *val_ptr;
> + const struct pm8941_wled_var_cfg *cfg;
> + } u32_opts[] = {
> + {
> + "qcom,current-boost-limit", &cfg->i_boost_limit,
> + .cfg = &pm8941_wled_i_boost_limit_cfg,
> + },
> + {
> + "qcom,current-limit", &cfg->i_limit,
> + .cfg = &pm8941_wled_i_limit_cfg,
> + },
> + {
> + "qcom,ovp", &cfg->ovp,
> + .cfg = &pm8941_wled_ovp_cfg,
> + },
> + {
> + "qcom,switching-freq", &cfg->switch_freq,
> + .cfg = &pm8941_wled_switch_freq_cfg,
> + },
> + {
> + "qcom,num-strings", &cfg->num_strings,
> + .cfg = &pm8941_wled_num_strings_cfg,
> + },
> + };
> + const struct {
> + const char *name;
> + bool *val_ptr;
> + } bool_opts[] = {
> + { "qcom,cs-out", &cfg->cs_out_en, },
> + { "qcom,ext-gen", &cfg->ext_gen, },
> + { "qcom,cabc", &cfg->cabc_en, },
> + };
> +
> + if (dev->of_node == NULL) {
> + dev_err(dev, "no OF node!\n");
> + return -EINVAL;
> + }
> +
> + rc = of_property_read_u32(dev->of_node, "reg", &val);
> + if (rc || val > 0xffff) {
> + dev_err(dev, "invalid IO resources\n");
> + return rc ? rc : -EINVAL;
> + }
> + wled->addr = val;
> +
> + rc = of_property_read_string(dev->of_node, "label", &wled->cdev.name);
> + if (rc)
> + wled->cdev.name = dev->of_node->name;
> +
> + wled->cdev.default_trigger = of_get_property(dev->of_node,
> + "linux,default-trigger", NULL);
> +
> + *cfg = pm8941_wled_config_defaults;
> + for (i = 0; i < ARRAY_SIZE(u32_opts); ++i) {
> + u32 sel, c;
> + int j, rj;
> +
> + rc = of_property_read_u32(dev->of_node, u32_opts[i].name, &val);
> + if (rc) {
> + if (rc != -EINVAL) {
> + dev_err(dev, "error reading '%s'\n",
> + u32_opts[i].name);
> + return rc;
> + }
> + continue;
> + }
> +
> + sel = UINT_MAX;
> + rj = -1;
> + c = pm8941_wled_values(u32_opts[i].cfg, 0);
> + for (j = 0; c != UINT_MAX; ++j) {
> + if (c <= val && (sel == UINT_MAX || c >= sel)) {
> + sel = c;
> + rj = j;
> + }
> + c = pm8941_wled_values(u32_opts[i].cfg, j + 1);
> + }
> + if (sel == UINT_MAX) {
> + dev_err(dev, "invalid value for '%s'\n",
> + u32_opts[i].name);
> + return rc;
> + }
> + if (sel != val) {
> + dev_warn(dev, "rounding '%s' down to %u\n",
> + u32_opts[i].name, sel);
> + }
> + dev_dbg(dev, "'%s' = %u\n", u32_opts[i].name, sel);
> + *u32_opts[i].val_ptr = rj;
> + };
> +
> + for (i = 0; i < ARRAY_SIZE(bool_opts); ++i) {
> + if (of_property_read_bool(dev->of_node, bool_opts[i].name))
> + *bool_opts[i].val_ptr = true;
> + }
> +
> + cfg->num_strings = cfg->num_strings + 1;
> +
> + return 0;
> +}
> +
> +static int pm8941_wled_probe(struct platform_device *pdev)
> +{
> + struct pm8941_wled_context *ctx;
> + struct regmap *regmap;
> + int rc;
> +
> + regmap = dev_get_regmap(pdev->dev.parent, NULL);
> + if (!regmap) {
> + dev_err(&pdev->dev, "Unable to get regmap\n");
> + return -EINVAL;
> + }
> +
Is this regmap mmio registers or i2c registers? Will the regmap
operation sleep?
> + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
> + if (ctx == NULL)
> + return -ENOMEM;
> +
> + ctx->regmap = regmap;
> +
> + rc = pm8941_wled_configure(&ctx->wled, &pdev->dev);
> + if (rc)
> + return rc;
> +
> + rc = pm8941_wled_setup(&ctx->wled);
> + if (rc)
> + return rc;
> +
> + ctx->wled.cdev.brightness_set = pm8941_wled_set_brightness;
> +
> + rc = led_classdev_register(&pdev->dev, &ctx->wled.cdev);
> + if (rc)
> + return rc;
> +
> + platform_set_drvdata(pdev, ctx);
> + dev_info(&pdev->dev, "registered led \"%s\"\n", ctx->wled.cdev.name);
> +
> + return 0;
> +};
> +
> +static int pm8941_wled_remove(struct platform_device *pdev)
> +{
> + struct pm8941_wled_context *ctx;
> +
> + ctx = platform_get_drvdata(pdev);
> + led_classdev_unregister(&ctx->wled.cdev);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id pm8941_wled_match_table[] = {
> + { .compatible = "qcom,pm8941-wled" },
> + {}
> +};
> +
> +static struct platform_driver pm8941_wled_driver = {
> + .probe = pm8941_wled_probe,
> + .remove = pm8941_wled_remove,
> + .driver = {
> + .name = "pm8941-wled",
> + .owner = THIS_MODULE,
> + .of_match_table = pm8941_wled_match_table,
> + },
> +};
> +
> +module_platform_driver(pm8941_wled_driver);
> +
> +MODULE_DESCRIPTION("pm8941 wled driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform: pm8941-wled");
No space after ":"
> --
> 1.8.2.2
>
On Tue, Dec 9, 2014 at 5:19 PM, Bryan Wu <[email protected]> wrote:
> On Mon, Dec 8, 2014 at 4:22 PM, Bjorn Andersson
> <[email protected]> wrote:
>> From: Courtney Cavin <[email protected]>
>>
>> This adds device tree binding documentation for the WLED ('White' LED)
>> block on Qualcomm's PM8941 PMICs.
>>
>
> Looks good to me, I need device tree reviewer's Ack to merge it.
>
Hi Rob, can you help to review it?
-Bryan
> Thanks,
> -Bryan
>
>> Signed-off-by: Courtney Cavin <[email protected]>
>> Signed-off-by: Bjorn Andersson <[email protected]>
>> ---
>> .../devicetree/bindings/leds/leds-pm8941-wled.txt | 43 ++++++++++++++++++++++
>> 1 file changed, 43 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt
>>
>> diff --git a/Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt b/Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt
>> new file mode 100644
>> index 0000000..a85a964
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt
>> @@ -0,0 +1,43 @@
>> +Binding for Qualcomm PM8941 WLED driver
>> +
>> +Required properties:
>> +- compatible: should be "qcom,pm8941-wled"
>> +- reg: slave address
>> +
>> +Optional properties:
>> +- label: The label for this led
>> + See Documentation/devicetree/bindings/leds/common.txt
>> +- linux,default-trigger: Default trigger assigned to the LED
>> + See Documentation/devicetree/bindings/leds/common.txt
>> +- qcom,cs-out: bool; enable current sink output
>> +- qcom,cabc: bool; enable content adaptive backlight control
>> +- qcom,ext-gen: bool; use externally generated modulator signal to dim
>> +- qcom,current-limit: mA; per-string current limit; value from 0 to 25
>> + default: 20mA
>> +- qcom,current-boost-limit: mA; boost current limit; one of:
>> + 105, 385, 525, 805, 980, 1260, 1400, 1680
>> + default: 805mA
>> +- qcom,switching-freq: kHz; switching frequency; one of:
>> + 600, 640, 685, 738, 800, 872, 960, 1066, 1200, 1371,
>> + 1600, 1920, 2400, 3200, 4800, 9600,
>> + default: 1600kHz
>> +- qcom,ovp: V; Over-voltage protection limit; one of:
>> + 27, 29, 32, 35
>> + default: 29V
>> +- qcom,num-strings: #; number of led strings attached; value from 1 to 3
>> + default: 2
>> +
>> +Example:
>> +
>> +pm8941-wled@d800 {
>> + compatible = "qcom,pm8941-wled";
>> + reg = <0xd800>;
>> + label = "backlight";
>> +
>> + qcom,cs-out;
>> + qcom,current-limit = <20>;
>> + qcom,current-boost-limit = <805>;
>> + qcom,switching-freq = <1600>;
>> + qcom,ovp = <29>;
>> + qcom,num-strings = <2>;
>> +};
>> --
>> 1.8.2.2
>>
On 12/08/2014 04:22 PM, Bjorn Andersson wrote:
> diff --git a/drivers/leds/leds-pm8941-wled.c b/drivers/leds/leds-pm8941-wled.c
> new file mode 100644
> index 0000000..aa06d0b
> --- /dev/null
> +++ b/drivers/leds/leds-pm8941-wled.c
> @@ -0,0 +1,466 @@
> +/* Copyright (c) 2013, Sony Mobile Communications, AB.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/leds.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/regmap.h>
Missing <linux/kernel.h> for container_of() macro.
> +
> +enum pm8941_wled_reg {
> + PM8941_WLED_REG_VAL_BASE = 0x40,
> +#define PM8941_WLED_REG_VAL_MAX 0xFFF
> +
> + PM8941_WLED_REG_MOD_EN = 0x46,
> +#define PM8941_WLED_REG_MOD_EN_BIT BIT(7)
> +#define PM8941_WLED_REG_MOD_EN_MASK BIT(7)
> +
> + PM8941_WLED_REG_SYNC = 0x47,
> +#define PM8941_WLED_REG_SYNC_MASK 0x07
> +#define PM8941_WLED_REG_SYNC_LED1 BIT(0)
> +#define PM8941_WLED_REG_SYNC_LED2 BIT(1)
> +#define PM8941_WLED_REG_SYNC_LED3 BIT(2)
> +#define PM8941_WLED_REG_SYNC_ALL 0x07
> +#define PM8941_WLED_REG_SYNC_CLEAR 0x00
> +
> + PM8941_WLED_REG_FREQ = 0x4c,
> +#define PM8941_WLED_REG_FREQ_MASK 0x0f
> +
> + PM8941_WLED_REG_OVP = 0x4d,
> +#define PM8941_WLED_REG_OVP_MASK 0x03
> +
> + PM8941_WLED_REG_BOOST = 0x4e,
> +#define PM8941_WLED_REG_BOOST_MASK 0x07
> +
> + PM8941_WLED_REG_SINK = 0x4f,
> +#define PM8941_WLED_REG_SINK_MASK 0xe0
> +#define PM8941_WLED_REG_SINK_SHFT 0x05
> +
> +/* Per-'string' registers below */
> +#define PM8941_WLED_REG_STR_OFFSET 0x10
> +
> + PM8941_WLED_REG_STR_MOD_EN_BASE = 0x60,
> +#define PM8941_WLED_REG_STR_MOD_EN BIT(7)
> +#define PM8941_WLED_REG_STR_MOD_MASK BIT(7)
> +
> + PM8941_WLED_REG_STR_SCALE_BASE = 0x62,
> +#define PM8941_WLED_REG_STR_SCALE_MASK 0x1f
> +
> + PM8941_WLED_REG_STR_MOD_SRC_BASE = 0x63,
> +#define PM8941_WLED_REG_STR_MOD_SRC_MASK 0x01
> +#define PM8941_WLED_REG_STR_MOD_SRC_INT 0x00
> +#define PM8941_WLED_REG_STR_MOD_SRC_EXT 0x01
> +
> + PM8941_WLED_REG_STR_CABC_BASE = 0x66,
> +#define PM8941_WLED_REG_STR_CABC_MASK BIT(7)
> +#define PM8941_WLED_REG_STR_CABC_EN BIT(7)
> +};
I don't see any value in this enum. It's never used in a switch
statement so why not just have #defines for the register offsets. It
would make reading this a lot easier too.
> +
> +static int pm8941_wled_set(struct led_classdev *cdev,
> + enum led_brightness value)
> +{
> + struct pm8941_wled_context *ctx;
> + struct pm8941_wled *wled;
> + u8 ctrl = 0;
> + u16 val;
> + int rc;
> + int i;
> +
> + wled = container_of(cdev, struct pm8941_wled, cdev);
> + ctx = container_of(wled, struct pm8941_wled_context, wled);
> +
> + if (value != 0)
> + ctrl = PM8941_WLED_REG_MOD_EN_BIT;
> +
> + val = (value * PM8941_WLED_REG_VAL_MAX) / LED_FULL;
Unnecessary parens here.
> +
> + rc = regmap_update_bits(ctx->regmap,
>
> +
> +static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
> +{
[...]
> +
> + if (dev->of_node == NULL) {
> + dev_err(dev, "no OF node!\n");
> + return -EINVAL;
> + }
Seems like an unnecessary check. Everything's DT so far.
> +
> + rc = of_property_read_u32(dev->of_node, "reg", &val);
> + if (rc || val > 0xffff) {
> + dev_err(dev, "invalid IO resources\n");
> + return rc ? rc : -EINVAL;
> + }
> + wled->addr = val;
> +
> + rc = of_property_read_string(dev->of_node, "label", &wled->cdev.name);
> + if (rc)
> + wled->cdev.name = dev->of_node->name;
> +
> + wled->cdev.default_trigger = of_get_property(dev->of_node,
> + "linux,default-trigger", NULL);
> +
> + *cfg = pm8941_wled_config_defaults;
> + for (i = 0; i < ARRAY_SIZE(u32_opts); ++i) {
> + u32 sel, c;
> + int j, rj;
> +
> + rc = of_property_read_u32(dev->of_node, u32_opts[i].name, &val);
> + if (rc) {
> + if (rc != -EINVAL) {
> + dev_err(dev, "error reading '%s'\n",
> + u32_opts[i].name);
> + return rc;
> + }
> + continue;
> + }
> +
> + sel = UINT_MAX;
> + rj = -1;
> + c = pm8941_wled_values(u32_opts[i].cfg, 0);
> + for (j = 0; c != UINT_MAX; ++j) {
> + if (c <= val && (sel == UINT_MAX || c >= sel)) {
> + sel = c;
> + rj = j;
> + }
> + c = pm8941_wled_values(u32_opts[i].cfg, j + 1);
> + }
> + if (sel == UINT_MAX) {
> + dev_err(dev, "invalid value for '%s'\n",
> + u32_opts[i].name);
> + return rc;
> + }
> + if (sel != val) {
> + dev_warn(dev, "rounding '%s' down to %u\n",
> + u32_opts[i].name, sel);
> + }
Do we really want to do all this complicated rounding and checking?
Can't we just assume the DT is correct?
> + dev_dbg(dev, "'%s' = %u\n", u32_opts[i].name, sel);
> + *u32_opts[i].val_ptr = rj;
> + };
> +
> + for (i = 0; i < ARRAY_SIZE(bool_opts); ++i) {
> + if (of_property_read_bool(dev->of_node, bool_opts[i].name))
> + *bool_opts[i].val_ptr = true;
> + }
> +
> + cfg->num_strings = cfg->num_strings + 1;
> +
> + return 0;
> +}
> +
> +static int pm8941_wled_probe(struct platform_device *pdev)
> +{
> + struct pm8941_wled_context *ctx;
> + struct regmap *regmap;
> + int rc;
> +
> + regmap = dev_get_regmap(pdev->dev.parent, NULL);
> + if (!regmap) {
> + dev_err(&pdev->dev, "Unable to get regmap\n");
> + return -EINVAL;
> + }
> +
> + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
> + if (ctx == NULL)
Nitpick only because it doesn't match the !regmap style above. Please
use the !ctx style here as well.
> + return -ENOMEM;
> +
> + ctx->regmap = regmap;
> +
> + rc = pm8941_wled_configure(&ctx->wled, &pdev->dev);
> + if (rc)
> + return rc;
> +
> + rc = pm8941_wled_setup(&ctx->wled);
> + if (rc)
> + return rc;
> +
> + ctx->wled.cdev.brightness_set = pm8941_wled_set_brightness;
> +
> + rc = led_classdev_register(&pdev->dev, &ctx->wled.cdev);
> + if (rc)
> + return rc;
> +
> + platform_set_drvdata(pdev, ctx);
> + dev_info(&pdev->dev, "registered led \"%s\"\n", ctx->wled.cdev.name);
Please don't spam the log with "I'm alive!" messages.
> +
> + return 0;
> +};
> +
> +static int pm8941_wled_remove(struct platform_device *pdev)
> +{
> + struct pm8941_wled_context *ctx;
> +
> + ctx = platform_get_drvdata(pdev);
> + led_classdev_unregister(&ctx->wled.cdev);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id pm8941_wled_match_table[] = {
> + { .compatible = "qcom,pm8941-wled" },
> + {}
> +};
MODULE_DEVICE_TABLE?
> +
> +static struct platform_driver pm8941_wled_driver = {
> + .probe = pm8941_wled_probe,
> + .remove = pm8941_wled_remove,
> + .driver = {
> + .name = "pm8941-wled",
> + .owner = THIS_MODULE,
> + .of_match_table = pm8941_wled_match_table,
> + },
> +};
> +
> +module_platform_driver(pm8941_wled_driver);
> +
> +MODULE_DESCRIPTION("pm8941 wled driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform: pm8941-wled");
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project
On 12/08/2014 04:22 PM, Bjorn Andersson wrote:
> +
> +Optional properties:
> +- label: The label for this led
> + See Documentation/devicetree/bindings/leds/common.txt
> +- linux,default-trigger: Default trigger assigned to the LED
> + See Documentation/devicetree/bindings/leds/common.txt
> +- qcom,cs-out: bool; enable current sink output
> +- qcom,cabc: bool; enable content adaptive backlight control
> +- qcom,ext-gen: bool; use externally generated modulator signal to dim
> +- qcom,current-limit: mA; per-string current limit; value from 0 to 25
> + default: 20mA
> +- qcom,current-boost-limit: mA; boost current limit; one of:
> + 105, 385, 525, 805, 980, 1260, 1400, 1680
> + default: 805mA
> +- qcom,switching-freq: kHz; switching frequency; one of:
> + 600, 640, 685, 738, 800, 872, 960, 1066, 1200, 1371,
> + 1600, 1920, 2400, 3200, 4800, 9600,
> + default: 1600kHz
> +- qcom,ovp: V; Over-voltage protection limit; one of:
> + 27, 29, 32, 35
> + default: 29V
It would be nice if the units were part of the property name, i.e.
qcom,ovp-V, qcom,current-boost-limit-mA, etc. That way the units are
known without having to refer to the documentation.
> +- qcom,num-strings: #; number of led strings attached; value from 1 to 3
> + default: 2
I wonder if qcom,#strings is more appropriate?
> +
> +Example:
> +
> +pm8941-wled@d800 {
> + compatible = "qcom,pm8941-wled";
> + reg = <0xd800>;
> + label = "backlight";
> +
> + qcom,cs-out;
> + qcom,current-limit = <20>;
> + qcom,current-boost-limit = <805>;
> + qcom,switching-freq = <1600>;
> + qcom,ovp = <29>;
> + qcom,num-strings = <2>;
> +};
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project
On Tue 16 Dec 17:15 PST 2014, Stephen Boyd wrote:
> On 12/08/2014 04:22 PM, Bjorn Andersson wrote:
>
[..]
> > +- qcom,current-limit: mA; per-string current limit; value from 0 to 25
> > + default: 20mA
> > +- qcom,current-boost-limit: mA; boost current limit; one of:
> > + 105, 385, 525, 805, 980, 1260, 1400, 1680
> > + default: 805mA
[..]
> > +- qcom,ovp: V; Over-voltage protection limit; one of:
> > + 27, 29, 32, 35
> > + default: 29V
>
> It would be nice if the units were part of the property name, i.e.
> qcom,ovp-V, qcom,current-boost-limit-mA, etc. That way the units are
> known without having to refer to the documentation.
>
That might be useful, on the other hand one probably need to look inte bindings
docs to figure out valid values anyways.
> > +- qcom,num-strings: #; number of led strings attached; value from 1 to 3
> > + default: 2
>
> I wonder if qcom,#strings is more appropriate?
>
Checking the other docs indicate that it's far more common to use num- than #
here, but I haven't found anything written about it - it's more common to name
this just "qcom,strings" than "qcom,#strings" at least...
Regards,
Bjorn
On Tue 16 Dec 16:54 PST 2014, Bryan Wu wrote:
> On Mon, Dec 8, 2014 at 4:22 PM, Bjorn Andersson
[..]
> > diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
[..]
> > +config LEDS_PM8941_WLED
> > + tristate "LED support for the Qualcomm PM8941 WLED block"
> > + depends on LEDS_CLASS
> > + depends on REGMAP
> Here should be "select REGMAP"
>
Thanks
> > + help
> > + This option enables support for the 'White' LED block
> > + on Qualcomm PM8941 PMICs.
> > +
[..]
> > diff --git a/drivers/leds/leds-pm8941-wled.c b/drivers/leds/leds-pm8941-wled.c
[..]
> > +
> > +struct pm8941_wled_context {
> > + struct pm8941_wled wled;
> > + struct regmap *regmap;
> > +};
> > +
>
> I think you can just add *regmap into pm8941_wled struct and
> pm8941_wled_context is redundant to me.
>
Looks like a development leftover, I will fold it in.
[..]
> > +
> > +static int pm8941_wled_probe(struct platform_device *pdev)
> > +{
> > + struct pm8941_wled_context *ctx;
> > + struct regmap *regmap;
> > + int rc;
> > +
> > + regmap = dev_get_regmap(pdev->dev.parent, NULL);
> > + if (!regmap) {
> > + dev_err(&pdev->dev, "Unable to get regmap\n");
> > + return -EINVAL;
> > + }
> > +
>
> Is this regmap mmio registers or i2c registers? Will the regmap
> operation sleep?
>
It's a spmi regmap, in it's current configuration it's marked as "fast" i.e. it
will not sleep.
I discussed this with Courtney before sending the patch out and as this is used
for backlight we don't see a reason calling set_brightness() in atomic context.
If this changes I would send out a follow up patch.
> > + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
> > + if (ctx == NULL)
> > + return -ENOMEM;
> > +
> > + ctx->regmap = regmap;
> > +
> > + rc = pm8941_wled_configure(&ctx->wled, &pdev->dev);
> > + if (rc)
> > + return rc;
> > +
> > + rc = pm8941_wled_setup(&ctx->wled);
> > + if (rc)
> > + return rc;
> > +
> > + ctx->wled.cdev.brightness_set = pm8941_wled_set_brightness;
> > +
> > + rc = led_classdev_register(&pdev->dev, &ctx->wled.cdev);
> > + if (rc)
> > + return rc;
> > +
> > + platform_set_drvdata(pdev, ctx);
> > + dev_info(&pdev->dev, "registered led \"%s\"\n", ctx->wled.cdev.name);
> > +
> > + return 0;
> > +};
> > +
[..]
> > +MODULE_DESCRIPTION("pm8941 wled driver");
> > +MODULE_LICENSE("GPL v2");
> > +MODULE_ALIAS("platform: pm8941-wled");
> No space after ":"
>
Oops.
Regards,
Bjorn
On Tue 16 Dec 17:15 PST 2014, Stephen Boyd wrote:
> On 12/08/2014 04:22 PM, Bjorn Andersson wrote:
> > diff --git a/drivers/leds/leds-pm8941-wled.c b/drivers/leds/leds-pm8941-wled.c
[..]
> > +#include <linux/leds.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_device.h>
> > +#include <linux/regmap.h>
>
> Missing <linux/kernel.h> for container_of() macro.
>
Thanks
> > +
> > +enum pm8941_wled_reg {
> > + PM8941_WLED_REG_VAL_BASE = 0x40,
> > +#define PM8941_WLED_REG_VAL_MAX 0xFFF
> > +
> > + PM8941_WLED_REG_MOD_EN = 0x46,
> > +#define PM8941_WLED_REG_MOD_EN_BIT BIT(7)
> > +#define PM8941_WLED_REG_MOD_EN_MASK BIT(7)
> > +
> > + PM8941_WLED_REG_SYNC = 0x47,
> > +#define PM8941_WLED_REG_SYNC_MASK 0x07
> > +#define PM8941_WLED_REG_SYNC_LED1 BIT(0)
> > +#define PM8941_WLED_REG_SYNC_LED2 BIT(1)
> > +#define PM8941_WLED_REG_SYNC_LED3 BIT(2)
> > +#define PM8941_WLED_REG_SYNC_ALL 0x07
> > +#define PM8941_WLED_REG_SYNC_CLEAR 0x00
> > +
> > + PM8941_WLED_REG_FREQ = 0x4c,
> > +#define PM8941_WLED_REG_FREQ_MASK 0x0f
> > +
> > + PM8941_WLED_REG_OVP = 0x4d,
> > +#define PM8941_WLED_REG_OVP_MASK 0x03
> > +
> > + PM8941_WLED_REG_BOOST = 0x4e,
> > +#define PM8941_WLED_REG_BOOST_MASK 0x07
> > +
> > + PM8941_WLED_REG_SINK = 0x4f,
> > +#define PM8941_WLED_REG_SINK_MASK 0xe0
> > +#define PM8941_WLED_REG_SINK_SHFT 0x05
> > +
> > +/* Per-'string' registers below */
> > +#define PM8941_WLED_REG_STR_OFFSET 0x10
> > +
> > + PM8941_WLED_REG_STR_MOD_EN_BASE = 0x60,
> > +#define PM8941_WLED_REG_STR_MOD_EN BIT(7)
> > +#define PM8941_WLED_REG_STR_MOD_MASK BIT(7)
> > +
> > + PM8941_WLED_REG_STR_SCALE_BASE = 0x62,
> > +#define PM8941_WLED_REG_STR_SCALE_MASK 0x1f
> > +
> > + PM8941_WLED_REG_STR_MOD_SRC_BASE = 0x63,
> > +#define PM8941_WLED_REG_STR_MOD_SRC_MASK 0x01
> > +#define PM8941_WLED_REG_STR_MOD_SRC_INT 0x00
> > +#define PM8941_WLED_REG_STR_MOD_SRC_EXT 0x01
> > +
> > + PM8941_WLED_REG_STR_CABC_BASE = 0x66,
> > +#define PM8941_WLED_REG_STR_CABC_MASK BIT(7)
> > +#define PM8941_WLED_REG_STR_CABC_EN BIT(7)
> > +};
>
> I don't see any value in this enum. It's never used in a switch
> statement so why not just have #defines for the register offsets. It
> would make reading this a lot easier too.
>
Make sense, I'll rework it.
> > +
> > +static int pm8941_wled_set(struct led_classdev *cdev,
> > + enum led_brightness value)
> > +{
> > + struct pm8941_wled_context *ctx;
> > + struct pm8941_wled *wled;
> > + u8 ctrl = 0;
> > + u16 val;
> > + int rc;
> > + int i;
> > +
> > + wled = container_of(cdev, struct pm8941_wled, cdev);
> > + ctx = container_of(wled, struct pm8941_wled_context, wled);
> > +
> > + if (value != 0)
> > + ctrl = PM8941_WLED_REG_MOD_EN_BIT;
> > +
> > + val = (value * PM8941_WLED_REG_VAL_MAX) / LED_FULL;
>
> Unnecessary parens here.
>
Agreed
> > +
> > + rc = regmap_update_bits(ctx->regmap,
> >
> > +
> > +static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
> > +{
> [...]
> > +
> > + if (dev->of_node == NULL) {
> > + dev_err(dev, "no OF node!\n");
> > + return -EINVAL;
> > + }
>
> Seems like an unnecessary check. Everything's DT so far.
>
Agreed.
> > +
> > + rc = of_property_read_u32(dev->of_node, "reg", &val);
> > + if (rc || val > 0xffff) {
> > + dev_err(dev, "invalid IO resources\n");
> > + return rc ? rc : -EINVAL;
> > + }
> > + wled->addr = val;
> > +
> > + rc = of_property_read_string(dev->of_node, "label", &wled->cdev.name);
> > + if (rc)
> > + wled->cdev.name = dev->of_node->name;
> > +
> > + wled->cdev.default_trigger = of_get_property(dev->of_node,
> > + "linux,default-trigger", NULL);
> > +
> > + *cfg = pm8941_wled_config_defaults;
> > + for (i = 0; i < ARRAY_SIZE(u32_opts); ++i) {
> > + u32 sel, c;
> > + int j, rj;
> > +
> > + rc = of_property_read_u32(dev->of_node, u32_opts[i].name, &val);
> > + if (rc) {
> > + if (rc != -EINVAL) {
> > + dev_err(dev, "error reading '%s'\n",
> > + u32_opts[i].name);
> > + return rc;
> > + }
> > + continue;
> > + }
> > +
> > + sel = UINT_MAX;
> > + rj = -1;
> > + c = pm8941_wled_values(u32_opts[i].cfg, 0);
> > + for (j = 0; c != UINT_MAX; ++j) {
> > + if (c <= val && (sel == UINT_MAX || c >= sel)) {
> > + sel = c;
> > + rj = j;
> > + }
> > + c = pm8941_wled_values(u32_opts[i].cfg, j + 1);
> > + }
> > + if (sel == UINT_MAX) {
> > + dev_err(dev, "invalid value for '%s'\n",
> > + u32_opts[i].name);
> > + return rc;
> > + }
> > + if (sel != val) {
> > + dev_warn(dev, "rounding '%s' down to %u\n",
> > + u32_opts[i].name, sel);
> > + }
>
> Do we really want to do all this complicated rounding and checking?
> Can't we just assume the DT is correct?
>
We could remove the printout about rounding, but the logic turns human-readable
values into register values (indices), so we need something for that.
> > + dev_dbg(dev, "'%s' = %u\n", u32_opts[i].name, sel);
> > + *u32_opts[i].val_ptr = rj;
> > + };
> > +
> > + for (i = 0; i < ARRAY_SIZE(bool_opts); ++i) {
> > + if (of_property_read_bool(dev->of_node, bool_opts[i].name))
> > + *bool_opts[i].val_ptr = true;
> > + }
> > +
> > + cfg->num_strings = cfg->num_strings + 1;
> > +
> > + return 0;
> > +}
> > +
> > +static int pm8941_wled_probe(struct platform_device *pdev)
> > +{
> > + struct pm8941_wled_context *ctx;
> > + struct regmap *regmap;
> > + int rc;
> > +
> > + regmap = dev_get_regmap(pdev->dev.parent, NULL);
> > + if (!regmap) {
> > + dev_err(&pdev->dev, "Unable to get regmap\n");
> > + return -EINVAL;
> > + }
> > +
> > + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
> > + if (ctx == NULL)
>
> Nitpick only because it doesn't match the !regmap style above. Please
> use the !ctx style here as well.
>
Agreed
> > + return -ENOMEM;
> > +
> > + ctx->regmap = regmap;
> > +
> > + rc = pm8941_wled_configure(&ctx->wled, &pdev->dev);
> > + if (rc)
> > + return rc;
> > +
> > + rc = pm8941_wled_setup(&ctx->wled);
> > + if (rc)
> > + return rc;
> > +
> > + ctx->wled.cdev.brightness_set = pm8941_wled_set_brightness;
> > +
> > + rc = led_classdev_register(&pdev->dev, &ctx->wled.cdev);
> > + if (rc)
> > + return rc;
> > +
> > + platform_set_drvdata(pdev, ctx);
> > + dev_info(&pdev->dev, "registered led \"%s\"\n", ctx->wled.cdev.name);
>
> Please don't spam the log with "I'm alive!" messages.
>
Ok
> > +
> > + return 0;
> > +};
> > +
[..]
> > +
> > +static const struct of_device_id pm8941_wled_match_table[] = {
> > + { .compatible = "qcom,pm8941-wled" },
> > + {}
> > +};
>
> MODULE_DEVICE_TABLE?
>
Indeed
Thanks for the review Stephen.
Regards,
Bjorn
On Thu, 2014-12-18 at 15:43 -0800, Bjorn wrote:
> On Tue 16 Dec 16:54 PST 2014, Bryan Wu wrote:
>
> > On Mon, Dec 8, 2014 at 4:22 PM, Bjorn Andersson
>
> [..]
>
> > > diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
>
> [..]
>
> > > +config LEDS_PM8941_WLED
> > > + tristate "LED support for the Qualcomm PM8941 WLED block"
> > > + depends on LEDS_CLASS
> > > + depends on REGMAP
> > Here should be "select REGMAP"
> >
>
> Thanks
> > >
If not mistaken the correct way was:
depends on SPMI
select REGMAP_SPMI
or
depends on MFD_SPMI_PMIC
Regards,
Ivan
https://patchwork.kernel.org/patch/4566591/