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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * MediaTek display pulse-width-modulation controller driver.
4 * Copyright (c) 2015 MediaTek Inc.
5 * Author: YH Huang <yh.huang@mediatek.com>
6 */
7
8#include <linux/bitfield.h>
9#include <linux/clk.h>
10#include <linux/err.h>
11#include <linux/io.h>
12#include <linux/module.h>
13#include <linux/of.h>
14#include <linux/platform_device.h>
15#include <linux/pwm.h>
16#include <linux/slab.h>
17
18#define DISP_PWM_EN 0x00
19
20#define PWM_CLKDIV_SHIFT 16
21#define PWM_CLKDIV_MAX 0x3ff
22#define PWM_CLKDIV_MASK (PWM_CLKDIV_MAX << PWM_CLKDIV_SHIFT)
23
24#define PWM_PERIOD_BIT_WIDTH 12
25#define PWM_PERIOD_MASK ((1 << PWM_PERIOD_BIT_WIDTH) - 1)
26
27#define PWM_HIGH_WIDTH_SHIFT 16
28#define PWM_HIGH_WIDTH_MASK (0x1fff << PWM_HIGH_WIDTH_SHIFT)
29
30struct mtk_pwm_data {
31 u32 enable_mask;
32 unsigned int con0;
33 u32 con0_sel;
34 unsigned int con1;
35
36 bool has_commit;
37 unsigned int commit;
38 unsigned int commit_mask;
39
40 unsigned int bls_debug;
41 u32 bls_debug_mask;
42};
43
44struct mtk_disp_pwm {
45 const struct mtk_pwm_data *data;
46 struct clk *clk_main;
47 struct clk *clk_mm;
48 void __iomem *base;
49 bool enabled;
50};
51
52static inline struct mtk_disp_pwm *to_mtk_disp_pwm(struct pwm_chip *chip)
53{
54 return pwmchip_get_drvdata(chip);
55}
56
57static void mtk_disp_pwm_update_bits(struct mtk_disp_pwm *mdp, u32 offset,
58 u32 mask, u32 data)
59{
60 void __iomem *address = mdp->base + offset;
61 u32 value;
62
63 value = readl(address);
64 value &= ~mask;
65 value |= data;
66 writel(value, address);
67}
68
69static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
70 const struct pwm_state *state)
71{
72 struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
73 u32 clk_div, period, high_width, value;
74 u64 div, rate;
75 int err;
76
77 if (state->polarity != PWM_POLARITY_NORMAL)
78 return -EINVAL;
79
80 if (!state->enabled && mdp->enabled) {
81 mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN,
82 mdp->data->enable_mask, 0x0);
83 clk_disable_unprepare(mdp->clk_mm);
84 clk_disable_unprepare(mdp->clk_main);
85
86 mdp->enabled = false;
87 return 0;
88 }
89
90 if (!mdp->enabled) {
91 err = clk_prepare_enable(mdp->clk_main);
92 if (err < 0) {
93 dev_err(pwmchip_parent(chip), "Can't enable mdp->clk_main: %pe\n",
94 ERR_PTR(err));
95 return err;
96 }
97
98 err = clk_prepare_enable(mdp->clk_mm);
99 if (err < 0) {
100 dev_err(pwmchip_parent(chip), "Can't enable mdp->clk_mm: %pe\n",
101 ERR_PTR(err));
102 clk_disable_unprepare(mdp->clk_main);
103 return err;
104 }
105 }
106
107 /*
108 * Find period, high_width and clk_div to suit duty_ns and period_ns.
109 * Calculate proper div value to keep period value in the bound.
110 *
111 * period_ns = 10^9 * (clk_div + 1) * (period + 1) / PWM_CLK_RATE
112 * duty_ns = 10^9 * (clk_div + 1) * high_width / PWM_CLK_RATE
113 *
114 * period = (PWM_CLK_RATE * period_ns) / (10^9 * (clk_div + 1)) - 1
115 * high_width = (PWM_CLK_RATE * duty_ns) / (10^9 * (clk_div + 1))
116 */
117 rate = clk_get_rate(mdp->clk_main);
118 clk_div = mul_u64_u64_div_u64(state->period, rate, NSEC_PER_SEC) >>
119 PWM_PERIOD_BIT_WIDTH;
120 if (clk_div > PWM_CLKDIV_MAX) {
121 if (!mdp->enabled) {
122 clk_disable_unprepare(mdp->clk_mm);
123 clk_disable_unprepare(mdp->clk_main);
124 }
125 return -EINVAL;
126 }
127
128 div = NSEC_PER_SEC * (clk_div + 1);
129 period = mul_u64_u64_div_u64(state->period, rate, div);
130 if (period > 0)
131 period--;
132
133 high_width = mul_u64_u64_div_u64(state->duty_cycle, rate, div);
134 value = period | (high_width << PWM_HIGH_WIDTH_SHIFT);
135
136 if (mdp->data->bls_debug && !mdp->data->has_commit) {
137 /*
138 * For MT2701, disable double buffer before writing register
139 * and select manual mode and use PWM_PERIOD/PWM_HIGH_WIDTH.
140 */
141 mtk_disp_pwm_update_bits(mdp, mdp->data->bls_debug,
142 mdp->data->bls_debug_mask,
143 mdp->data->bls_debug_mask);
144 mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
145 mdp->data->con0_sel,
146 mdp->data->con0_sel);
147 }
148
149 mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
150 PWM_CLKDIV_MASK,
151 clk_div << PWM_CLKDIV_SHIFT);
152 mtk_disp_pwm_update_bits(mdp, mdp->data->con1,
153 PWM_PERIOD_MASK | PWM_HIGH_WIDTH_MASK,
154 value);
155
156 if (mdp->data->has_commit) {
157 mtk_disp_pwm_update_bits(mdp, mdp->data->commit,
158 mdp->data->commit_mask,
159 mdp->data->commit_mask);
160 mtk_disp_pwm_update_bits(mdp, mdp->data->commit,
161 mdp->data->commit_mask,
162 0x0);
163 }
164
165 mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
166 mdp->data->enable_mask);
167 mdp->enabled = true;
168
169 return 0;
170}
171
172static int mtk_disp_pwm_get_state(struct pwm_chip *chip,
173 struct pwm_device *pwm,
174 struct pwm_state *state)
175{
176 struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
177 u64 rate, period, high_width;
178 u32 clk_div, pwm_en, con0, con1;
179 int err;
180
181 err = clk_prepare_enable(mdp->clk_main);
182 if (err < 0) {
183 dev_err(pwmchip_parent(chip), "Can't enable mdp->clk_main: %pe\n", ERR_PTR(err));
184 return err;
185 }
186
187 err = clk_prepare_enable(mdp->clk_mm);
188 if (err < 0) {
189 dev_err(pwmchip_parent(chip), "Can't enable mdp->clk_mm: %pe\n", ERR_PTR(err));
190 clk_disable_unprepare(mdp->clk_main);
191 return err;
192 }
193
194 /*
195 * Apply DISP_PWM_DEBUG settings to choose whether to enable or disable
196 * registers double buffer and manual commit to working register before
197 * performing any read/write operation
198 */
199 if (mdp->data->bls_debug)
200 mtk_disp_pwm_update_bits(mdp, mdp->data->bls_debug,
201 mdp->data->bls_debug_mask,
202 mdp->data->bls_debug_mask);
203
204 rate = clk_get_rate(mdp->clk_main);
205 con0 = readl(mdp->base + mdp->data->con0);
206 con1 = readl(mdp->base + mdp->data->con1);
207 pwm_en = readl(mdp->base + DISP_PWM_EN);
208 state->enabled = !!(pwm_en & mdp->data->enable_mask);
209 clk_div = FIELD_GET(PWM_CLKDIV_MASK, con0);
210 period = FIELD_GET(PWM_PERIOD_MASK, con1);
211 /*
212 * period has 12 bits, clk_div 11 and NSEC_PER_SEC has 30,
213 * so period * (clk_div + 1) * NSEC_PER_SEC doesn't overflow.
214 */
215 state->period = DIV64_U64_ROUND_UP(period * (clk_div + 1) * NSEC_PER_SEC, rate);
216 high_width = FIELD_GET(PWM_HIGH_WIDTH_MASK, con1);
217 state->duty_cycle = DIV64_U64_ROUND_UP(high_width * (clk_div + 1) * NSEC_PER_SEC,
218 rate);
219 state->polarity = PWM_POLARITY_NORMAL;
220 clk_disable_unprepare(mdp->clk_mm);
221 clk_disable_unprepare(mdp->clk_main);
222
223 return 0;
224}
225
226static const struct pwm_ops mtk_disp_pwm_ops = {
227 .apply = mtk_disp_pwm_apply,
228 .get_state = mtk_disp_pwm_get_state,
229};
230
231static int mtk_disp_pwm_probe(struct platform_device *pdev)
232{
233 struct pwm_chip *chip;
234 struct mtk_disp_pwm *mdp;
235 int ret;
236
237 chip = devm_pwmchip_alloc(&pdev->dev, 1, sizeof(*mdp));
238 if (IS_ERR(chip))
239 return PTR_ERR(chip);
240 mdp = to_mtk_disp_pwm(chip);
241
242 mdp->data = of_device_get_match_data(&pdev->dev);
243
244 mdp->base = devm_platform_ioremap_resource(pdev, 0);
245 if (IS_ERR(mdp->base))
246 return PTR_ERR(mdp->base);
247
248 mdp->clk_main = devm_clk_get(&pdev->dev, "main");
249 if (IS_ERR(mdp->clk_main))
250 return dev_err_probe(&pdev->dev, PTR_ERR(mdp->clk_main),
251 "Failed to get main clock\n");
252
253 mdp->clk_mm = devm_clk_get(&pdev->dev, "mm");
254 if (IS_ERR(mdp->clk_mm))
255 return dev_err_probe(&pdev->dev, PTR_ERR(mdp->clk_mm),
256 "Failed to get mm clock\n");
257
258 chip->ops = &mtk_disp_pwm_ops;
259
260 ret = devm_pwmchip_add(&pdev->dev, chip);
261 if (ret < 0)
262 return dev_err_probe(&pdev->dev, ret, "pwmchip_add() failed\n");
263
264 return 0;
265}
266
267static const struct mtk_pwm_data mt2701_pwm_data = {
268 .enable_mask = BIT(16),
269 .con0 = 0xa8,
270 .con0_sel = 0x2,
271 .con1 = 0xac,
272 .has_commit = false,
273 .bls_debug = 0xb0,
274 .bls_debug_mask = 0x3,
275};
276
277static const struct mtk_pwm_data mt8173_pwm_data = {
278 .enable_mask = BIT(0),
279 .con0 = 0x10,
280 .con0_sel = 0x0,
281 .con1 = 0x14,
282 .has_commit = true,
283 .commit = 0x8,
284 .commit_mask = 0x1,
285};
286
287static const struct mtk_pwm_data mt8183_pwm_data = {
288 .enable_mask = BIT(0),
289 .con0 = 0x18,
290 .con0_sel = 0x0,
291 .con1 = 0x1c,
292 .has_commit = false,
293 .bls_debug = 0x80,
294 .bls_debug_mask = 0x3,
295};
296
297static const struct of_device_id mtk_disp_pwm_of_match[] = {
298 { .compatible = "mediatek,mt2701-disp-pwm", .data = &mt2701_pwm_data},
299 { .compatible = "mediatek,mt6595-disp-pwm", .data = &mt8173_pwm_data},
300 { .compatible = "mediatek,mt8173-disp-pwm", .data = &mt8173_pwm_data},
301 { .compatible = "mediatek,mt8183-disp-pwm", .data = &mt8183_pwm_data},
302 { }
303};
304MODULE_DEVICE_TABLE(of, mtk_disp_pwm_of_match);
305
306static struct platform_driver mtk_disp_pwm_driver = {
307 .driver = {
308 .name = "mediatek-disp-pwm",
309 .of_match_table = mtk_disp_pwm_of_match,
310 },
311 .probe = mtk_disp_pwm_probe,
312};
313module_platform_driver(mtk_disp_pwm_driver);
314
315MODULE_AUTHOR("YH Huang <yh.huang@mediatek.com>");
316MODULE_DESCRIPTION("MediaTek SoC display PWM driver");
317MODULE_LICENSE("GPL v2");
1/*
2 * MediaTek display pulse-width-modulation controller driver.
3 * Copyright (c) 2015 MediaTek Inc.
4 * Author: YH Huang <yh.huang@mediatek.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16#include <linux/clk.h>
17#include <linux/err.h>
18#include <linux/io.h>
19#include <linux/module.h>
20#include <linux/of.h>
21#include <linux/of_device.h>
22#include <linux/platform_device.h>
23#include <linux/pwm.h>
24#include <linux/slab.h>
25
26#define DISP_PWM_EN 0x00
27
28#define PWM_CLKDIV_SHIFT 16
29#define PWM_CLKDIV_MAX 0x3ff
30#define PWM_CLKDIV_MASK (PWM_CLKDIV_MAX << PWM_CLKDIV_SHIFT)
31
32#define PWM_PERIOD_BIT_WIDTH 12
33#define PWM_PERIOD_MASK ((1 << PWM_PERIOD_BIT_WIDTH) - 1)
34
35#define PWM_HIGH_WIDTH_SHIFT 16
36#define PWM_HIGH_WIDTH_MASK (0x1fff << PWM_HIGH_WIDTH_SHIFT)
37
38struct mtk_pwm_data {
39 u32 enable_mask;
40 unsigned int con0;
41 u32 con0_sel;
42 unsigned int con1;
43
44 bool has_commit;
45 unsigned int commit;
46 unsigned int commit_mask;
47
48 unsigned int bls_debug;
49 u32 bls_debug_mask;
50};
51
52struct mtk_disp_pwm {
53 struct pwm_chip chip;
54 const struct mtk_pwm_data *data;
55 struct clk *clk_main;
56 struct clk *clk_mm;
57 void __iomem *base;
58};
59
60static inline struct mtk_disp_pwm *to_mtk_disp_pwm(struct pwm_chip *chip)
61{
62 return container_of(chip, struct mtk_disp_pwm, chip);
63}
64
65static void mtk_disp_pwm_update_bits(struct mtk_disp_pwm *mdp, u32 offset,
66 u32 mask, u32 data)
67{
68 void __iomem *address = mdp->base + offset;
69 u32 value;
70
71 value = readl(address);
72 value &= ~mask;
73 value |= data;
74 writel(value, address);
75}
76
77static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
78 int duty_ns, int period_ns)
79{
80 struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
81 u32 clk_div, period, high_width, value;
82 u64 div, rate;
83 int err;
84
85 /*
86 * Find period, high_width and clk_div to suit duty_ns and period_ns.
87 * Calculate proper div value to keep period value in the bound.
88 *
89 * period_ns = 10^9 * (clk_div + 1) * (period + 1) / PWM_CLK_RATE
90 * duty_ns = 10^9 * (clk_div + 1) * high_width / PWM_CLK_RATE
91 *
92 * period = (PWM_CLK_RATE * period_ns) / (10^9 * (clk_div + 1)) - 1
93 * high_width = (PWM_CLK_RATE * duty_ns) / (10^9 * (clk_div + 1))
94 */
95 rate = clk_get_rate(mdp->clk_main);
96 clk_div = div_u64(rate * period_ns, NSEC_PER_SEC) >>
97 PWM_PERIOD_BIT_WIDTH;
98 if (clk_div > PWM_CLKDIV_MAX)
99 return -EINVAL;
100
101 div = NSEC_PER_SEC * (clk_div + 1);
102 period = div64_u64(rate * period_ns, div);
103 if (period > 0)
104 period--;
105
106 high_width = div64_u64(rate * duty_ns, div);
107 value = period | (high_width << PWM_HIGH_WIDTH_SHIFT);
108
109 err = clk_enable(mdp->clk_main);
110 if (err < 0)
111 return err;
112
113 err = clk_enable(mdp->clk_mm);
114 if (err < 0) {
115 clk_disable(mdp->clk_main);
116 return err;
117 }
118
119 mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
120 PWM_CLKDIV_MASK,
121 clk_div << PWM_CLKDIV_SHIFT);
122 mtk_disp_pwm_update_bits(mdp, mdp->data->con1,
123 PWM_PERIOD_MASK | PWM_HIGH_WIDTH_MASK,
124 value);
125
126 if (mdp->data->has_commit) {
127 mtk_disp_pwm_update_bits(mdp, mdp->data->commit,
128 mdp->data->commit_mask,
129 mdp->data->commit_mask);
130 mtk_disp_pwm_update_bits(mdp, mdp->data->commit,
131 mdp->data->commit_mask,
132 0x0);
133 }
134
135 clk_disable(mdp->clk_mm);
136 clk_disable(mdp->clk_main);
137
138 return 0;
139}
140
141static int mtk_disp_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
142{
143 struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
144 int err;
145
146 err = clk_enable(mdp->clk_main);
147 if (err < 0)
148 return err;
149
150 err = clk_enable(mdp->clk_mm);
151 if (err < 0) {
152 clk_disable(mdp->clk_main);
153 return err;
154 }
155
156 mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
157 mdp->data->enable_mask);
158
159 return 0;
160}
161
162static void mtk_disp_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
163{
164 struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
165
166 mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
167 0x0);
168
169 clk_disable(mdp->clk_mm);
170 clk_disable(mdp->clk_main);
171}
172
173static const struct pwm_ops mtk_disp_pwm_ops = {
174 .config = mtk_disp_pwm_config,
175 .enable = mtk_disp_pwm_enable,
176 .disable = mtk_disp_pwm_disable,
177 .owner = THIS_MODULE,
178};
179
180static int mtk_disp_pwm_probe(struct platform_device *pdev)
181{
182 struct mtk_disp_pwm *mdp;
183 struct resource *r;
184 int ret;
185
186 mdp = devm_kzalloc(&pdev->dev, sizeof(*mdp), GFP_KERNEL);
187 if (!mdp)
188 return -ENOMEM;
189
190 mdp->data = of_device_get_match_data(&pdev->dev);
191
192 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
193 mdp->base = devm_ioremap_resource(&pdev->dev, r);
194 if (IS_ERR(mdp->base))
195 return PTR_ERR(mdp->base);
196
197 mdp->clk_main = devm_clk_get(&pdev->dev, "main");
198 if (IS_ERR(mdp->clk_main))
199 return PTR_ERR(mdp->clk_main);
200
201 mdp->clk_mm = devm_clk_get(&pdev->dev, "mm");
202 if (IS_ERR(mdp->clk_mm))
203 return PTR_ERR(mdp->clk_mm);
204
205 ret = clk_prepare(mdp->clk_main);
206 if (ret < 0)
207 return ret;
208
209 ret = clk_prepare(mdp->clk_mm);
210 if (ret < 0)
211 goto disable_clk_main;
212
213 mdp->chip.dev = &pdev->dev;
214 mdp->chip.ops = &mtk_disp_pwm_ops;
215 mdp->chip.base = -1;
216 mdp->chip.npwm = 1;
217
218 ret = pwmchip_add(&mdp->chip);
219 if (ret < 0) {
220 dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
221 goto disable_clk_mm;
222 }
223
224 platform_set_drvdata(pdev, mdp);
225
226 /*
227 * For MT2701, disable double buffer before writing register
228 * and select manual mode and use PWM_PERIOD/PWM_HIGH_WIDTH.
229 */
230 if (!mdp->data->has_commit) {
231 mtk_disp_pwm_update_bits(mdp, mdp->data->bls_debug,
232 mdp->data->bls_debug_mask,
233 mdp->data->bls_debug_mask);
234 mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
235 mdp->data->con0_sel,
236 mdp->data->con0_sel);
237 }
238
239 return 0;
240
241disable_clk_mm:
242 clk_unprepare(mdp->clk_mm);
243disable_clk_main:
244 clk_unprepare(mdp->clk_main);
245 return ret;
246}
247
248static int mtk_disp_pwm_remove(struct platform_device *pdev)
249{
250 struct mtk_disp_pwm *mdp = platform_get_drvdata(pdev);
251 int ret;
252
253 ret = pwmchip_remove(&mdp->chip);
254 clk_unprepare(mdp->clk_mm);
255 clk_unprepare(mdp->clk_main);
256
257 return ret;
258}
259
260static const struct mtk_pwm_data mt2701_pwm_data = {
261 .enable_mask = BIT(16),
262 .con0 = 0xa8,
263 .con0_sel = 0x2,
264 .con1 = 0xac,
265 .has_commit = false,
266 .bls_debug = 0xb0,
267 .bls_debug_mask = 0x3,
268};
269
270static const struct mtk_pwm_data mt8173_pwm_data = {
271 .enable_mask = BIT(0),
272 .con0 = 0x10,
273 .con0_sel = 0x0,
274 .con1 = 0x14,
275 .has_commit = true,
276 .commit = 0x8,
277 .commit_mask = 0x1,
278};
279
280static const struct of_device_id mtk_disp_pwm_of_match[] = {
281 { .compatible = "mediatek,mt2701-disp-pwm", .data = &mt2701_pwm_data},
282 { .compatible = "mediatek,mt6595-disp-pwm", .data = &mt8173_pwm_data},
283 { .compatible = "mediatek,mt8173-disp-pwm", .data = &mt8173_pwm_data},
284 { }
285};
286MODULE_DEVICE_TABLE(of, mtk_disp_pwm_of_match);
287
288static struct platform_driver mtk_disp_pwm_driver = {
289 .driver = {
290 .name = "mediatek-disp-pwm",
291 .of_match_table = mtk_disp_pwm_of_match,
292 },
293 .probe = mtk_disp_pwm_probe,
294 .remove = mtk_disp_pwm_remove,
295};
296module_platform_driver(mtk_disp_pwm_driver);
297
298MODULE_AUTHOR("YH Huang <yh.huang@mediatek.com>");
299MODULE_DESCRIPTION("MediaTek SoC display PWM driver");
300MODULE_LICENSE("GPL v2");