Lines Matching +full:pwm +full:- +full:active +full:- +full:state
1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
4 * JZ4740 platform PWM support
7 * - The .apply callback doesn't complete the currently running period before
15 #include <linux/mfd/ingenic-tcu.h>
20 #include <linux/pwm.h>
41 /* Enable all TCU channels for PWM use by default except channels 0/1 */ in jz4740_pwm_can_use_chn()
42 u32 pwm_channels_mask = GENMASK(jz->chip.npwm - 1, 2); in jz4740_pwm_can_use_chn()
44 device_property_read_u32(jz->chip.dev->parent, in jz4740_pwm_can_use_chn()
45 "ingenic,pwm-channels-mask", in jz4740_pwm_can_use_chn()
51 static int jz4740_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) in jz4740_pwm_request() argument
58 if (!jz4740_pwm_can_use_chn(jz, pwm->hwpwm)) in jz4740_pwm_request()
59 return -EBUSY; in jz4740_pwm_request()
61 snprintf(name, sizeof(name), "timer%u", pwm->hwpwm); in jz4740_pwm_request()
63 clk = clk_get(chip->dev, name); in jz4740_pwm_request()
65 dev_err(chip->dev, "error %pe: Failed to get clock\n", clk); in jz4740_pwm_request()
75 jz->clk[pwm->hwpwm] = clk; in jz4740_pwm_request()
80 static void jz4740_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) in jz4740_pwm_free() argument
83 struct clk *clk = jz->clk[pwm->hwpwm]; in jz4740_pwm_free()
89 static int jz4740_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) in jz4740_pwm_enable() argument
93 /* Enable PWM output */ in jz4740_pwm_enable()
94 regmap_set_bits(jz->map, TCU_REG_TCSRc(pwm->hwpwm), TCU_TCSR_PWM_EN); in jz4740_pwm_enable()
97 regmap_write(jz->map, TCU_REG_TESR, BIT(pwm->hwpwm)); in jz4740_pwm_enable()
102 static void jz4740_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) in jz4740_pwm_disable() argument
110 regmap_write(jz->map, TCU_REG_TDHRc(pwm->hwpwm), 0xffff); in jz4740_pwm_disable()
111 regmap_write(jz->map, TCU_REG_TDFRc(pwm->hwpwm), 0x0); in jz4740_pwm_disable()
114 * Disable PWM output. in jz4740_pwm_disable()
118 regmap_clear_bits(jz->map, TCU_REG_TCSRc(pwm->hwpwm), TCU_TCSR_PWM_EN); in jz4740_pwm_disable()
121 regmap_write(jz->map, TCU_REG_TECR, BIT(pwm->hwpwm)); in jz4740_pwm_disable()
124 static int jz4740_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, in jz4740_pwm_apply() argument
125 const struct pwm_state *state) in jz4740_pwm_apply() argument
129 struct clk *clk = jz->clk[pwm->hwpwm]; in jz4740_pwm_apply()
138 do_div(tmp, state->period); in jz4740_pwm_apply()
142 * ------------------- in jz4740_pwm_apply()
148 * round-down function (and won't have one for a while), but if it ever in jz4740_pwm_apply()
149 * comes to light, a round-down function should be used instead. in jz4740_pwm_apply()
153 dev_err(chip->dev, "Unable to round rate: %ld\n", rate); in jz4740_pwm_apply()
158 tmp = (unsigned long long)rate * state->period; in jz4740_pwm_apply()
163 tmp = (unsigned long long)rate * state->duty_cycle; in jz4740_pwm_apply()
168 duty = period - 1; in jz4740_pwm_apply()
170 jz4740_pwm_disable(chip, pwm); in jz4740_pwm_apply()
174 dev_err(chip->dev, "Unable to set rate: %d\n", err); in jz4740_pwm_apply()
179 regmap_write(jz->map, TCU_REG_TCNTc(pwm->hwpwm), 0); in jz4740_pwm_apply()
182 regmap_write(jz->map, TCU_REG_TDHRc(pwm->hwpwm), duty); in jz4740_pwm_apply()
185 regmap_write(jz->map, TCU_REG_TDFRc(pwm->hwpwm), period); in jz4740_pwm_apply()
188 regmap_set_bits(jz->map, TCU_REG_TCSRc(pwm->hwpwm), in jz4740_pwm_apply()
194 * The PWM starts in inactive state until the internal timer reaches the in jz4740_pwm_apply()
195 * duty value, then becomes active until the timer reaches the period in jz4740_pwm_apply()
196 * value. In theory, we should then use (period - duty) as the real duty in jz4740_pwm_apply()
197 * value, as a high duty value would otherwise result in the PWM pin in jz4740_pwm_apply()
200 * Here, we don't do that, and instead invert the polarity of the PWM in jz4740_pwm_apply()
201 * when it is active. This trick makes the PWM start with its active in jz4740_pwm_apply()
202 * state instead of its inactive state. in jz4740_pwm_apply()
204 if ((state->polarity == PWM_POLARITY_NORMAL) ^ state->enabled) in jz4740_pwm_apply()
205 regmap_update_bits(jz->map, TCU_REG_TCSRc(pwm->hwpwm), in jz4740_pwm_apply()
208 regmap_update_bits(jz->map, TCU_REG_TCSRc(pwm->hwpwm), in jz4740_pwm_apply()
212 if (state->enabled) in jz4740_pwm_apply()
213 jz4740_pwm_enable(chip, pwm); in jz4740_pwm_apply()
226 struct device *dev = &pdev->dev; in jz4740_pwm_probe()
232 return -EINVAL; in jz4740_pwm_probe()
234 jz = devm_kzalloc(dev, struct_size(jz, clk, info->num_pwms), in jz4740_pwm_probe()
237 return -ENOMEM; in jz4740_pwm_probe()
239 jz->map = device_node_to_regmap(dev->parent->of_node); in jz4740_pwm_probe()
240 if (IS_ERR(jz->map)) { in jz4740_pwm_probe()
241 dev_err(dev, "regmap not found: %ld\n", PTR_ERR(jz->map)); in jz4740_pwm_probe()
242 return PTR_ERR(jz->map); in jz4740_pwm_probe()
245 jz->chip.dev = dev; in jz4740_pwm_probe()
246 jz->chip.ops = &jz4740_pwm_ops; in jz4740_pwm_probe()
247 jz->chip.npwm = info->num_pwms; in jz4740_pwm_probe()
249 return devm_pwmchip_add(dev, &jz->chip); in jz4740_pwm_probe()
265 { .compatible = "ingenic,jz4740-pwm", .data = &jz4740_soc_info },
266 { .compatible = "ingenic,jz4725b-pwm", .data = &jz4725b_soc_info },
267 { .compatible = "ingenic,x1000-pwm", .data = &x1000_soc_info },
274 .name = "jz4740-pwm",
281 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
282 MODULE_DESCRIPTION("Ingenic JZ4740 PWM driver");
283 MODULE_ALIAS("platform:jz4740-pwm");