1 /* Copyright (c) 2015, Sony Mobile Communications, AB.
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License version 2 and
5 * only version 2 as published by the Free Software Foundation.
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
13 #include <linux/kernel.h>
14 #include <linux/backlight.h>
15 #include <linux/module.h>
17 #include <linux/of_device.h>
18 #include <linux/regmap.h>
20 #define PM8941_WLED_REG_VAL_BASE 0x40
21 #define PM8941_WLED_REG_VAL_MAX 0xFFF
23 #define PM8941_WLED_REG_MOD_EN 0x46
24 #define PM8941_WLED_REG_MOD_EN_BIT BIT(7)
25 #define PM8941_WLED_REG_MOD_EN_MASK BIT(7)
27 #define PM8941_WLED_REG_SYNC 0x47
28 #define PM8941_WLED_REG_SYNC_MASK 0x07
29 #define PM8941_WLED_REG_SYNC_LED1 BIT(0)
30 #define PM8941_WLED_REG_SYNC_LED2 BIT(1)
31 #define PM8941_WLED_REG_SYNC_LED3 BIT(2)
32 #define PM8941_WLED_REG_SYNC_ALL 0x07
33 #define PM8941_WLED_REG_SYNC_CLEAR 0x00
35 #define PM8941_WLED_REG_FREQ 0x4c
36 #define PM8941_WLED_REG_FREQ_MASK 0x0f
38 #define PM8941_WLED_REG_OVP 0x4d
39 #define PM8941_WLED_REG_OVP_MASK 0x03
41 #define PM8941_WLED_REG_BOOST 0x4e
42 #define PM8941_WLED_REG_BOOST_MASK 0x07
44 #define PM8941_WLED_REG_SINK 0x4f
45 #define PM8941_WLED_REG_SINK_MASK 0xe0
46 #define PM8941_WLED_REG_SINK_SHFT 0x05
48 /* Per-'string' registers below */
49 #define PM8941_WLED_REG_STR_OFFSET 0x10
51 #define PM8941_WLED_REG_STR_MOD_EN_BASE 0x60
52 #define PM8941_WLED_REG_STR_MOD_MASK BIT(7)
53 #define PM8941_WLED_REG_STR_MOD_EN BIT(7)
55 #define PM8941_WLED_REG_STR_SCALE_BASE 0x62
56 #define PM8941_WLED_REG_STR_SCALE_MASK 0x1f
58 #define PM8941_WLED_REG_STR_MOD_SRC_BASE 0x63
59 #define PM8941_WLED_REG_STR_MOD_SRC_MASK 0x01
60 #define PM8941_WLED_REG_STR_MOD_SRC_INT 0x00
61 #define PM8941_WLED_REG_STR_MOD_SRC_EXT 0x01
63 #define PM8941_WLED_REG_STR_CABC_BASE 0x66
64 #define PM8941_WLED_REG_STR_CABC_MASK BIT(7)
65 #define PM8941_WLED_REG_STR_CABC_EN BIT(7)
67 struct pm8941_wled_config {
80 struct regmap *regmap;
83 struct pm8941_wled_config cfg;
86 static int pm8941_wled_update_status(struct backlight_device *bl)
88 struct pm8941_wled *wled = bl_get_data(bl);
89 u16 val = bl->props.brightness;
94 if (bl->props.power != FB_BLANK_UNBLANK ||
95 bl->props.fb_blank != FB_BLANK_UNBLANK ||
96 bl->props.state & BL_CORE_FBBLANK)
100 ctrl = PM8941_WLED_REG_MOD_EN_BIT;
102 rc = regmap_update_bits(wled->regmap,
103 wled->addr + PM8941_WLED_REG_MOD_EN,
104 PM8941_WLED_REG_MOD_EN_MASK, ctrl);
108 for (i = 0; i < wled->cfg.num_strings; ++i) {
109 u8 v[2] = { val & 0xff, (val >> 8) & 0xf };
111 rc = regmap_bulk_write(wled->regmap,
112 wled->addr + PM8941_WLED_REG_VAL_BASE + 2 * i,
118 rc = regmap_update_bits(wled->regmap,
119 wled->addr + PM8941_WLED_REG_SYNC,
120 PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_ALL);
124 rc = regmap_update_bits(wled->regmap,
125 wled->addr + PM8941_WLED_REG_SYNC,
126 PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_CLEAR);
130 static int pm8941_wled_setup(struct pm8941_wled *wled)
135 rc = regmap_update_bits(wled->regmap,
136 wled->addr + PM8941_WLED_REG_OVP,
137 PM8941_WLED_REG_OVP_MASK, wled->cfg.ovp);
141 rc = regmap_update_bits(wled->regmap,
142 wled->addr + PM8941_WLED_REG_BOOST,
143 PM8941_WLED_REG_BOOST_MASK, wled->cfg.i_boost_limit);
147 rc = regmap_update_bits(wled->regmap,
148 wled->addr + PM8941_WLED_REG_FREQ,
149 PM8941_WLED_REG_FREQ_MASK, wled->cfg.switch_freq);
153 if (wled->cfg.cs_out_en) {
154 u8 all = (BIT(wled->cfg.num_strings) - 1)
155 << PM8941_WLED_REG_SINK_SHFT;
157 rc = regmap_update_bits(wled->regmap,
158 wled->addr + PM8941_WLED_REG_SINK,
159 PM8941_WLED_REG_SINK_MASK, all);
164 for (i = 0; i < wled->cfg.num_strings; ++i) {
165 u16 addr = wled->addr + PM8941_WLED_REG_STR_OFFSET * i;
167 rc = regmap_update_bits(wled->regmap,
168 addr + PM8941_WLED_REG_STR_MOD_EN_BASE,
169 PM8941_WLED_REG_STR_MOD_MASK,
170 PM8941_WLED_REG_STR_MOD_EN);
174 if (wled->cfg.ext_gen) {
175 rc = regmap_update_bits(wled->regmap,
176 addr + PM8941_WLED_REG_STR_MOD_SRC_BASE,
177 PM8941_WLED_REG_STR_MOD_SRC_MASK,
178 PM8941_WLED_REG_STR_MOD_SRC_EXT);
183 rc = regmap_update_bits(wled->regmap,
184 addr + PM8941_WLED_REG_STR_SCALE_BASE,
185 PM8941_WLED_REG_STR_SCALE_MASK,
190 rc = regmap_update_bits(wled->regmap,
191 addr + PM8941_WLED_REG_STR_CABC_BASE,
192 PM8941_WLED_REG_STR_CABC_MASK,
194 PM8941_WLED_REG_STR_CABC_EN : 0);
202 static const struct pm8941_wled_config pm8941_wled_config_defaults = {
213 struct pm8941_wled_var_cfg {
219 static const u32 pm8941_wled_i_boost_limit_values[] = {
220 105, 385, 525, 805, 980, 1260, 1400, 1680,
223 static const struct pm8941_wled_var_cfg pm8941_wled_i_boost_limit_cfg = {
224 .values = pm8941_wled_i_boost_limit_values,
225 .size = ARRAY_SIZE(pm8941_wled_i_boost_limit_values),
228 static const u32 pm8941_wled_ovp_values[] = {
232 static const struct pm8941_wled_var_cfg pm8941_wled_ovp_cfg = {
233 .values = pm8941_wled_ovp_values,
234 .size = ARRAY_SIZE(pm8941_wled_ovp_values),
237 static u32 pm8941_wled_num_strings_values_fn(u32 idx)
242 static const struct pm8941_wled_var_cfg pm8941_wled_num_strings_cfg = {
243 .fn = pm8941_wled_num_strings_values_fn,
247 static u32 pm8941_wled_switch_freq_values_fn(u32 idx)
249 return 19200 / (2 * (1 + idx));
252 static const struct pm8941_wled_var_cfg pm8941_wled_switch_freq_cfg = {
253 .fn = pm8941_wled_switch_freq_values_fn,
257 static const struct pm8941_wled_var_cfg pm8941_wled_i_limit_cfg = {
261 static u32 pm8941_wled_values(const struct pm8941_wled_var_cfg *cfg, u32 idx)
263 if (idx >= cfg->size)
268 return cfg->values[idx];
272 static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
274 struct pm8941_wled_config *cfg = &wled->cfg;
284 const struct pm8941_wled_var_cfg *cfg;
287 "qcom,current-boost-limit",
289 .cfg = &pm8941_wled_i_boost_limit_cfg,
292 "qcom,current-limit",
294 .cfg = &pm8941_wled_i_limit_cfg,
299 .cfg = &pm8941_wled_ovp_cfg,
302 "qcom,switching-freq",
304 .cfg = &pm8941_wled_switch_freq_cfg,
309 .cfg = &pm8941_wled_num_strings_cfg,
316 { "qcom,cs-out", &cfg->cs_out_en, },
317 { "qcom,ext-gen", &cfg->ext_gen, },
318 { "qcom,cabc", &cfg->cabc_en, },
321 rc = of_property_read_u32(dev->of_node, "reg", &val);
322 if (rc || val > 0xffff) {
323 dev_err(dev, "invalid IO resources\n");
324 return rc ? rc : -EINVAL;
328 rc = of_property_read_string(dev->of_node, "label", &wled->name);
330 wled->name = dev->of_node->name;
332 *cfg = pm8941_wled_config_defaults;
333 for (i = 0; i < ARRAY_SIZE(u32_opts); ++i) {
334 rc = of_property_read_u32(dev->of_node, u32_opts[i].name, &val);
338 dev_err(dev, "error reading '%s'\n", u32_opts[i].name);
343 for (j = 0; c != val; j++) {
344 c = pm8941_wled_values(u32_opts[i].cfg, j);
346 dev_err(dev, "invalid value for '%s'\n",
352 dev_dbg(dev, "'%s' = %u\n", u32_opts[i].name, c);
353 *u32_opts[i].val_ptr = j;
356 for (i = 0; i < ARRAY_SIZE(bool_opts); ++i) {
357 if (of_property_read_bool(dev->of_node, bool_opts[i].name))
358 *bool_opts[i].val_ptr = true;
361 cfg->num_strings = cfg->num_strings + 1;
366 static const struct backlight_ops pm8941_wled_ops = {
367 .update_status = pm8941_wled_update_status,
370 static int pm8941_wled_probe(struct platform_device *pdev)
372 struct backlight_properties props;
373 struct backlight_device *bl;
374 struct pm8941_wled *wled;
375 struct regmap *regmap;
378 regmap = dev_get_regmap(pdev->dev.parent, NULL);
380 dev_err(&pdev->dev, "Unable to get regmap\n");
384 wled = devm_kzalloc(&pdev->dev, sizeof(*wled), GFP_KERNEL);
388 wled->regmap = regmap;
390 rc = pm8941_wled_configure(wled, &pdev->dev);
394 rc = pm8941_wled_setup(wled);
398 memset(&props, 0, sizeof(struct backlight_properties));
399 props.type = BACKLIGHT_RAW;
400 props.max_brightness = PM8941_WLED_REG_VAL_MAX;
401 bl = devm_backlight_device_register(&pdev->dev, wled->name,
403 &pm8941_wled_ops, &props);
410 static const struct of_device_id pm8941_wled_match_table[] = {
411 { .compatible = "qcom,pm8941-wled" },
414 MODULE_DEVICE_TABLE(of, pm8941_wled_match_table);
416 static struct platform_driver pm8941_wled_driver = {
417 .probe = pm8941_wled_probe,
419 .name = "pm8941-wled",
420 .of_match_table = pm8941_wled_match_table,
424 module_platform_driver(pm8941_wled_driver);
426 MODULE_DESCRIPTION("pm8941 wled driver");
427 MODULE_LICENSE("GPL v2");