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1// SPDX-License-Identifier: GPL-2.0
2// TI LM36274 LED chip family driver
3// Copyright (C) 2019 Texas Instruments Incorporated - https://www.ti.com/
4
5#include <linux/bitops.h>
6#include <linux/device.h>
7#include <linux/err.h>
8#include <linux/leds.h>
9#include <linux/leds-ti-lmu-common.h>
10#include <linux/mod_devicetable.h>
11#include <linux/module.h>
12#include <linux/platform_device.h>
13#include <linux/property.h>
14
15#include <linux/mfd/ti-lmu.h>
16#include <linux/mfd/ti-lmu-register.h>
17
18#include <uapi/linux/uleds.h>
19
20#define LM36274_MAX_STRINGS 4
21#define LM36274_BL_EN BIT(4)
22
23/**
24 * struct lm36274
25 * @pdev: platform device
26 * @led_dev: led class device
27 * @lmu_data: Register and setting values for common code
28 * @regmap: Devices register map
29 * @dev: Pointer to the devices device struct
30 * @led_sources: The LED strings supported in this array
31 * @num_leds: Number of LED strings are supported in this array
32 */
33struct lm36274 {
34 struct platform_device *pdev;
35 struct led_classdev led_dev;
36 struct ti_lmu_bank lmu_data;
37 struct regmap *regmap;
38 struct device *dev;
39
40 u32 led_sources[LM36274_MAX_STRINGS];
41 int num_leds;
42};
43
44static int lm36274_brightness_set(struct led_classdev *led_cdev,
45 enum led_brightness brt_val)
46{
47 struct lm36274 *chip = container_of(led_cdev, struct lm36274, led_dev);
48
49 return ti_lmu_common_set_brightness(&chip->lmu_data, brt_val);
50}
51
52static int lm36274_init(struct lm36274 *chip)
53{
54 int enable_val = 0;
55 int i;
56
57 for (i = 0; i < chip->num_leds; i++)
58 enable_val |= (1 << chip->led_sources[i]);
59
60 if (!enable_val) {
61 dev_err(chip->dev, "No LEDs were enabled\n");
62 return -EINVAL;
63 }
64
65 enable_val |= LM36274_BL_EN;
66
67 return regmap_write(chip->regmap, LM36274_REG_BL_EN, enable_val);
68}
69
70static int lm36274_parse_dt(struct lm36274 *chip,
71 struct led_init_data *init_data)
72{
73 struct device *dev = chip->dev;
74 struct fwnode_handle *child;
75 int ret;
76
77 /* There should only be 1 node */
78 if (device_get_child_node_count(dev) != 1)
79 return -EINVAL;
80
81 child = device_get_next_child_node(dev, NULL);
82
83 init_data->fwnode = child;
84 init_data->devicename = chip->pdev->name;
85 /* for backwards compatibility when `label` property is not present */
86 init_data->default_label = ":";
87
88 chip->num_leds = fwnode_property_count_u32(child, "led-sources");
89 if (chip->num_leds <= 0) {
90 ret = -ENODEV;
91 goto err;
92 }
93
94 ret = fwnode_property_read_u32_array(child, "led-sources",
95 chip->led_sources, chip->num_leds);
96 if (ret) {
97 dev_err(dev, "led-sources property missing\n");
98 goto err;
99 }
100
101 return 0;
102err:
103 fwnode_handle_put(child);
104 return ret;
105}
106
107static int lm36274_probe(struct platform_device *pdev)
108{
109 struct ti_lmu *lmu = dev_get_drvdata(pdev->dev.parent);
110 struct led_init_data init_data = {};
111 struct lm36274 *chip;
112 int ret;
113
114 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
115 if (!chip)
116 return -ENOMEM;
117
118 chip->pdev = pdev;
119 chip->dev = &pdev->dev;
120 chip->regmap = lmu->regmap;
121 platform_set_drvdata(pdev, chip);
122
123 ret = lm36274_parse_dt(chip, &init_data);
124 if (ret) {
125 dev_err(chip->dev, "Failed to parse DT node\n");
126 return ret;
127 }
128
129 ret = lm36274_init(chip);
130 if (ret) {
131 fwnode_handle_put(init_data.fwnode);
132 dev_err(chip->dev, "Failed to init the device\n");
133 return ret;
134 }
135
136 chip->lmu_data.regmap = chip->regmap;
137 chip->lmu_data.max_brightness = MAX_BRIGHTNESS_11BIT;
138 chip->lmu_data.msb_brightness_reg = LM36274_REG_BRT_MSB;
139 chip->lmu_data.lsb_brightness_reg = LM36274_REG_BRT_LSB;
140
141 chip->led_dev.max_brightness = MAX_BRIGHTNESS_11BIT;
142 chip->led_dev.brightness_set_blocking = lm36274_brightness_set;
143
144 ret = devm_led_classdev_register_ext(chip->dev, &chip->led_dev,
145 &init_data);
146 if (ret)
147 dev_err(chip->dev, "Failed to register LED for node %pfw\n",
148 init_data.fwnode);
149
150 fwnode_handle_put(init_data.fwnode);
151
152 return ret;
153}
154
155static const struct of_device_id of_lm36274_leds_match[] = {
156 { .compatible = "ti,lm36274-backlight", },
157 {},
158};
159MODULE_DEVICE_TABLE(of, of_lm36274_leds_match);
160
161static struct platform_driver lm36274_driver = {
162 .probe = lm36274_probe,
163 .driver = {
164 .name = "lm36274-leds",
165 .of_match_table = of_lm36274_leds_match,
166 },
167};
168module_platform_driver(lm36274_driver)
169
170MODULE_DESCRIPTION("Texas Instruments LM36274 LED driver");
171MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
172MODULE_LICENSE("GPL v2");
1// SPDX-License-Identifier: GPL-2.0
2// TI LM36274 LED chip family driver
3// Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
4
5#include <linux/bitops.h>
6#include <linux/device.h>
7#include <linux/err.h>
8#include <linux/leds.h>
9#include <linux/leds-ti-lmu-common.h>
10#include <linux/module.h>
11#include <linux/of_device.h>
12#include <linux/platform_device.h>
13
14#include <linux/mfd/ti-lmu.h>
15#include <linux/mfd/ti-lmu-register.h>
16
17#include <uapi/linux/uleds.h>
18
19#define LM36274_MAX_STRINGS 4
20#define LM36274_BL_EN BIT(4)
21
22/**
23 * struct lm36274
24 * @pdev: platform device
25 * @led_dev: led class device
26 * @lmu_data: Register and setting values for common code
27 * @regmap: Devices register map
28 * @dev: Pointer to the devices device struct
29 * @led_sources - The LED strings supported in this array
30 * @num_leds - Number of LED strings are supported in this array
31 */
32struct lm36274 {
33 struct platform_device *pdev;
34 struct led_classdev led_dev;
35 struct ti_lmu_bank lmu_data;
36 struct regmap *regmap;
37 struct device *dev;
38
39 u32 led_sources[LM36274_MAX_STRINGS];
40 int num_leds;
41};
42
43static int lm36274_brightness_set(struct led_classdev *led_cdev,
44 enum led_brightness brt_val)
45{
46 struct lm36274 *led = container_of(led_cdev, struct lm36274, led_dev);
47
48 return ti_lmu_common_set_brightness(&led->lmu_data, brt_val);
49}
50
51static int lm36274_init(struct lm36274 *lm36274_data)
52{
53 int enable_val = 0;
54 int i;
55
56 for (i = 0; i < lm36274_data->num_leds; i++)
57 enable_val |= (1 << lm36274_data->led_sources[i]);
58
59 if (!enable_val) {
60 dev_err(lm36274_data->dev, "No LEDs were enabled\n");
61 return -EINVAL;
62 }
63
64 enable_val |= LM36274_BL_EN;
65
66 return regmap_write(lm36274_data->regmap, LM36274_REG_BL_EN,
67 enable_val);
68}
69
70static int lm36274_parse_dt(struct lm36274 *lm36274_data)
71{
72 struct fwnode_handle *child = NULL;
73 char label[LED_MAX_NAME_SIZE];
74 struct device *dev = &lm36274_data->pdev->dev;
75 const char *name;
76 int child_cnt;
77 int ret = -EINVAL;
78
79 /* There should only be 1 node */
80 child_cnt = device_get_child_node_count(dev);
81 if (child_cnt != 1)
82 return -EINVAL;
83
84 device_for_each_child_node(dev, child) {
85 ret = fwnode_property_read_string(child, "label", &name);
86 if (ret)
87 snprintf(label, sizeof(label),
88 "%s::", lm36274_data->pdev->name);
89 else
90 snprintf(label, sizeof(label),
91 "%s:%s", lm36274_data->pdev->name, name);
92
93 lm36274_data->num_leds = fwnode_property_count_u32(child, "led-sources");
94 if (lm36274_data->num_leds <= 0)
95 return -ENODEV;
96
97 ret = fwnode_property_read_u32_array(child, "led-sources",
98 lm36274_data->led_sources,
99 lm36274_data->num_leds);
100 if (ret) {
101 dev_err(dev, "led-sources property missing\n");
102 return ret;
103 }
104
105 fwnode_property_read_string(child, "linux,default-trigger",
106 &lm36274_data->led_dev.default_trigger);
107
108 }
109
110 lm36274_data->lmu_data.regmap = lm36274_data->regmap;
111 lm36274_data->lmu_data.max_brightness = MAX_BRIGHTNESS_11BIT;
112 lm36274_data->lmu_data.msb_brightness_reg = LM36274_REG_BRT_MSB;
113 lm36274_data->lmu_data.lsb_brightness_reg = LM36274_REG_BRT_LSB;
114
115 lm36274_data->led_dev.name = label;
116 lm36274_data->led_dev.max_brightness = MAX_BRIGHTNESS_11BIT;
117 lm36274_data->led_dev.brightness_set_blocking = lm36274_brightness_set;
118
119 return 0;
120}
121
122static int lm36274_probe(struct platform_device *pdev)
123{
124 struct ti_lmu *lmu = dev_get_drvdata(pdev->dev.parent);
125 struct lm36274 *lm36274_data;
126 int ret;
127
128 lm36274_data = devm_kzalloc(&pdev->dev, sizeof(*lm36274_data),
129 GFP_KERNEL);
130 if (!lm36274_data)
131 return -ENOMEM;
132
133 lm36274_data->pdev = pdev;
134 lm36274_data->dev = lmu->dev;
135 lm36274_data->regmap = lmu->regmap;
136 dev_set_drvdata(&pdev->dev, lm36274_data);
137
138 ret = lm36274_parse_dt(lm36274_data);
139 if (ret) {
140 dev_err(lm36274_data->dev, "Failed to parse DT node\n");
141 return ret;
142 }
143
144 ret = lm36274_init(lm36274_data);
145 if (ret) {
146 dev_err(lm36274_data->dev, "Failed to init the device\n");
147 return ret;
148 }
149
150 return devm_led_classdev_register(lm36274_data->dev,
151 &lm36274_data->led_dev);
152}
153
154static const struct of_device_id of_lm36274_leds_match[] = {
155 { .compatible = "ti,lm36274-backlight", },
156 {},
157};
158MODULE_DEVICE_TABLE(of, of_lm36274_leds_match);
159
160static struct platform_driver lm36274_driver = {
161 .probe = lm36274_probe,
162 .driver = {
163 .name = "lm36274-leds",
164 },
165};
166module_platform_driver(lm36274_driver)
167
168MODULE_DESCRIPTION("Texas Instruments LM36274 LED driver");
169MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
170MODULE_LICENSE("GPL v2");