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>
21 #define PM8941_WLED_DEFAULT_BRIGHTNESS 2048
23 #define PM8941_WLED_REG_VAL_BASE 0x40
24 #define PM8941_WLED_REG_VAL_MAX 0xFFF
26 #define PM8941_WLED_REG_MOD_EN 0x46
27 #define PM8941_WLED_REG_MOD_EN_BIT BIT(7)
28 #define PM8941_WLED_REG_MOD_EN_MASK BIT(7)
30 #define PM8941_WLED_REG_SYNC 0x47
31 #define PM8941_WLED_REG_SYNC_MASK 0x07
32 #define PM8941_WLED_REG_SYNC_LED1 BIT(0)
33 #define PM8941_WLED_REG_SYNC_LED2 BIT(1)
34 #define PM8941_WLED_REG_SYNC_LED3 BIT(2)
35 #define PM8941_WLED_REG_SYNC_ALL 0x07
36 #define PM8941_WLED_REG_SYNC_CLEAR 0x00
38 #define PM8941_WLED_REG_FREQ 0x4c
39 #define PM8941_WLED_REG_FREQ_MASK 0x0f
41 #define PM8941_WLED_REG_OVP 0x4d
42 #define PM8941_WLED_REG_OVP_MASK 0x03
44 #define PM8941_WLED_REG_BOOST 0x4e
45 #define PM8941_WLED_REG_BOOST_MASK 0x07
47 #define PM8941_WLED_REG_SINK 0x4f
48 #define PM8941_WLED_REG_SINK_MASK 0xe0
49 #define PM8941_WLED_REG_SINK_SHFT 0x05
51 /* Per-'string' registers below */
52 #define PM8941_WLED_REG_STR_OFFSET 0x10
54 #define PM8941_WLED_REG_STR_MOD_EN_BASE 0x60
55 #define PM8941_WLED_REG_STR_MOD_MASK BIT(7)
56 #define PM8941_WLED_REG_STR_MOD_EN BIT(7)
58 #define PM8941_WLED_REG_STR_SCALE_BASE 0x62
59 #define PM8941_WLED_REG_STR_SCALE_MASK 0x1f
61 #define PM8941_WLED_REG_STR_MOD_SRC_BASE 0x63
62 #define PM8941_WLED_REG_STR_MOD_SRC_MASK 0x01
63 #define PM8941_WLED_REG_STR_MOD_SRC_INT 0x00
64 #define PM8941_WLED_REG_STR_MOD_SRC_EXT 0x01
66 #define PM8941_WLED_REG_STR_CABC_BASE 0x66
67 #define PM8941_WLED_REG_STR_CABC_MASK BIT(7)
68 #define PM8941_WLED_REG_STR_CABC_EN BIT(7)
70 struct pm8941_wled_config {
83 struct regmap *regmap;
86 struct pm8941_wled_config cfg;
89 static int pm8941_wled_update_status(struct backlight_device *bl)
91 struct pm8941_wled *wled = bl_get_data(bl);
92 u16 val = bl->props.brightness;
97 if (bl->props.power != FB_BLANK_UNBLANK ||
98 bl->props.fb_blank != FB_BLANK_UNBLANK ||
99 bl->props.state & BL_CORE_FBBLANK)
103 ctrl = PM8941_WLED_REG_MOD_EN_BIT;
105 rc = regmap_update_bits(wled->regmap,
106 wled->addr + PM8941_WLED_REG_MOD_EN,
107 PM8941_WLED_REG_MOD_EN_MASK, ctrl);
111 for (i = 0; i < wled->cfg.num_strings; ++i) {
112 u8 v[2] = { val & 0xff, (val >> 8) & 0xf };
114 rc = regmap_bulk_write(wled->regmap,
115 wled->addr + PM8941_WLED_REG_VAL_BASE + 2 * i,
121 rc = regmap_update_bits(wled->regmap,
122 wled->addr + PM8941_WLED_REG_SYNC,
123 PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_ALL);
127 rc = regmap_update_bits(wled->regmap,
128 wled->addr + PM8941_WLED_REG_SYNC,
129 PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_CLEAR);
133 static int pm8941_wled_setup(struct pm8941_wled *wled)
138 rc = regmap_update_bits(wled->regmap,
139 wled->addr + PM8941_WLED_REG_OVP,
140 PM8941_WLED_REG_OVP_MASK, wled->cfg.ovp);
144 rc = regmap_update_bits(wled->regmap,
145 wled->addr + PM8941_WLED_REG_BOOST,
146 PM8941_WLED_REG_BOOST_MASK, wled->cfg.i_boost_limit);
150 rc = regmap_update_bits(wled->regmap,
151 wled->addr + PM8941_WLED_REG_FREQ,
152 PM8941_WLED_REG_FREQ_MASK, wled->cfg.switch_freq);
156 if (wled->cfg.cs_out_en) {
157 u8 all = (BIT(wled->cfg.num_strings) - 1)
158 << PM8941_WLED_REG_SINK_SHFT;
160 rc = regmap_update_bits(wled->regmap,
161 wled->addr + PM8941_WLED_REG_SINK,
162 PM8941_WLED_REG_SINK_MASK, all);
167 for (i = 0; i < wled->cfg.num_strings; ++i) {
168 u16 addr = wled->addr + PM8941_WLED_REG_STR_OFFSET * i;
170 rc = regmap_update_bits(wled->regmap,
171 addr + PM8941_WLED_REG_STR_MOD_EN_BASE,
172 PM8941_WLED_REG_STR_MOD_MASK,
173 PM8941_WLED_REG_STR_MOD_EN);
177 if (wled->cfg.ext_gen) {
178 rc = regmap_update_bits(wled->regmap,
179 addr + PM8941_WLED_REG_STR_MOD_SRC_BASE,
180 PM8941_WLED_REG_STR_MOD_SRC_MASK,
181 PM8941_WLED_REG_STR_MOD_SRC_EXT);
186 rc = regmap_update_bits(wled->regmap,
187 addr + PM8941_WLED_REG_STR_SCALE_BASE,
188 PM8941_WLED_REG_STR_SCALE_MASK,
193 rc = regmap_update_bits(wled->regmap,
194 addr + PM8941_WLED_REG_STR_CABC_BASE,
195 PM8941_WLED_REG_STR_CABC_MASK,
197 PM8941_WLED_REG_STR_CABC_EN : 0);
205 static const struct pm8941_wled_config pm8941_wled_config_defaults = {
216 struct pm8941_wled_var_cfg {
222 static const u32 pm8941_wled_i_boost_limit_values[] = {
223 105, 385, 525, 805, 980, 1260, 1400, 1680,
226 static const struct pm8941_wled_var_cfg pm8941_wled_i_boost_limit_cfg = {
227 .values = pm8941_wled_i_boost_limit_values,
228 .size = ARRAY_SIZE(pm8941_wled_i_boost_limit_values),
231 static const u32 pm8941_wled_ovp_values[] = {
235 static const struct pm8941_wled_var_cfg pm8941_wled_ovp_cfg = {
236 .values = pm8941_wled_ovp_values,
237 .size = ARRAY_SIZE(pm8941_wled_ovp_values),
240 static u32 pm8941_wled_num_strings_values_fn(u32 idx)
245 static const struct pm8941_wled_var_cfg pm8941_wled_num_strings_cfg = {
246 .fn = pm8941_wled_num_strings_values_fn,
250 static u32 pm8941_wled_switch_freq_values_fn(u32 idx)
252 return 19200 / (2 * (1 + idx));
255 static const struct pm8941_wled_var_cfg pm8941_wled_switch_freq_cfg = {
256 .fn = pm8941_wled_switch_freq_values_fn,
260 static const struct pm8941_wled_var_cfg pm8941_wled_i_limit_cfg = {
264 static u32 pm8941_wled_values(const struct pm8941_wled_var_cfg *cfg, u32 idx)
266 if (idx >= cfg->size)
271 return cfg->values[idx];
275 static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
277 struct pm8941_wled_config *cfg = &wled->cfg;
287 const struct pm8941_wled_var_cfg *cfg;
290 "qcom,current-boost-limit",
292 .cfg = &pm8941_wled_i_boost_limit_cfg,
295 "qcom,current-limit",
297 .cfg = &pm8941_wled_i_limit_cfg,
302 .cfg = &pm8941_wled_ovp_cfg,
305 "qcom,switching-freq",
307 .cfg = &pm8941_wled_switch_freq_cfg,
312 .cfg = &pm8941_wled_num_strings_cfg,
319 { "qcom,cs-out", &cfg->cs_out_en, },
320 { "qcom,ext-gen", &cfg->ext_gen, },
321 { "qcom,cabc", &cfg->cabc_en, },
324 rc = of_property_read_u32(dev->of_node, "reg", &val);
325 if (rc || val > 0xffff) {
326 dev_err(dev, "invalid IO resources\n");
327 return rc ? rc : -EINVAL;
331 rc = of_property_read_string(dev->of_node, "label", &wled->name);
333 wled->name = dev->of_node->name;
335 *cfg = pm8941_wled_config_defaults;
336 for (i = 0; i < ARRAY_SIZE(u32_opts); ++i) {
337 rc = of_property_read_u32(dev->of_node, u32_opts[i].name, &val);
341 dev_err(dev, "error reading '%s'\n", u32_opts[i].name);
346 for (j = 0; c != val; j++) {
347 c = pm8941_wled_values(u32_opts[i].cfg, j);
349 dev_err(dev, "invalid value for '%s'\n",
355 dev_dbg(dev, "'%s' = %u\n", u32_opts[i].name, c);
356 *u32_opts[i].val_ptr = j;
359 for (i = 0; i < ARRAY_SIZE(bool_opts); ++i) {
360 if (of_property_read_bool(dev->of_node, bool_opts[i].name))
361 *bool_opts[i].val_ptr = true;
364 cfg->num_strings = cfg->num_strings + 1;
369 static const struct backlight_ops pm8941_wled_ops = {
370 .update_status = pm8941_wled_update_status,
373 static int pm8941_wled_probe(struct platform_device *pdev)
375 struct backlight_properties props;
376 struct backlight_device *bl;
377 struct pm8941_wled *wled;
378 struct regmap *regmap;
382 regmap = dev_get_regmap(pdev->dev.parent, NULL);
384 dev_err(&pdev->dev, "Unable to get regmap\n");
388 wled = devm_kzalloc(&pdev->dev, sizeof(*wled), GFP_KERNEL);
392 wled->regmap = regmap;
394 rc = pm8941_wled_configure(wled, &pdev->dev);
398 rc = pm8941_wled_setup(wled);
402 val = PM8941_WLED_DEFAULT_BRIGHTNESS;
403 of_property_read_u32(pdev->dev.of_node, "default-brightness", &val);
405 memset(&props, 0, sizeof(struct backlight_properties));
406 props.type = BACKLIGHT_RAW;
407 props.brightness = val;
408 props.max_brightness = PM8941_WLED_REG_VAL_MAX;
409 bl = devm_backlight_device_register(&pdev->dev, wled->name,
411 &pm8941_wled_ops, &props);
412 return PTR_ERR_OR_ZERO(bl);
415 static const struct of_device_id pm8941_wled_match_table[] = {
416 { .compatible = "qcom,pm8941-wled" },
419 MODULE_DEVICE_TABLE(of, pm8941_wled_match_table);
421 static struct platform_driver pm8941_wled_driver = {
422 .probe = pm8941_wled_probe,
424 .name = "pm8941-wled",
425 .of_match_table = pm8941_wled_match_table,
429 module_platform_driver(pm8941_wled_driver);
431 MODULE_DESCRIPTION("pm8941 wled driver");
432 MODULE_LICENSE("GPL v2");