1 // SPDX-License-Identifier: GPL-2.0
3  * Analog Devices AXI PWM generator
11  * - The writes to registers for period and duty are shadowed until
14  * - Writing LOAD_CONFIG also has the effect of re-synchronizing all
18  * - Supports normal polarity. Does not support changing polarity.
19  * - On disable, the PWM output becomes low (inactive).
21 #include <linux/adi-axi-common.h>
80 	if (wf->period_length_ns == 0) {  in axi_pwmgen_round_waveform_tohw()
87 		/* With ddata->clk_rate_hz < NSEC_PER_SEC this won't overflow. */  in axi_pwmgen_round_waveform_tohw()
88 		wfhw->period_cnt = min_t(u64,  in axi_pwmgen_round_waveform_tohw()
89 					 mul_u64_u32_div(wf->period_length_ns, ddata->clk_rate_hz, NSEC_PER_SEC),  in axi_pwmgen_round_waveform_tohw()
92 		if (wfhw->period_cnt == 0) {  in axi_pwmgen_round_waveform_tohw()
100 			wfhw->period_cnt = 1;  in axi_pwmgen_round_waveform_tohw()
101 			wfhw->duty_cycle_cnt = 0;  in axi_pwmgen_round_waveform_tohw()
102 			wfhw->duty_offset_cnt = 0;  in axi_pwmgen_round_waveform_tohw()
105 			wfhw->duty_cycle_cnt = min_t(u64,  in axi_pwmgen_round_waveform_tohw()
106 						     mul_u64_u32_div(wf->duty_length_ns, ddata->clk_rate_hz, NSEC_PER_SEC),  in axi_pwmgen_round_waveform_tohw()
108 			wfhw->duty_offset_cnt = min_t(u64,  in axi_pwmgen_round_waveform_tohw()
109 						      mul_u64_u32_div(wf->duty_offset_ns, ddata->clk_rate_hz, NSEC_PER_SEC),  in axi_pwmgen_round_waveform_tohw()
114 	dev_dbg(&chip->dev, "pwm#%u: %lld/%lld [+%lld] @%lu -> PERIOD: %08x, DUTY: %08x, OFFSET: %08x\n",  in axi_pwmgen_round_waveform_tohw()
115 		pwm->hwpwm, wf->duty_length_ns, wf->period_length_ns, wf->duty_offset_ns,  in axi_pwmgen_round_waveform_tohw()
116 		ddata->clk_rate_hz, wfhw->period_cnt, wfhw->duty_cycle_cnt, wfhw->duty_offset_cnt);  in axi_pwmgen_round_waveform_tohw()
127 	wf->period_length_ns = DIV64_U64_ROUND_UP((u64)wfhw->period_cnt * NSEC_PER_SEC,  in axi_pwmgen_round_waveform_fromhw()
128 					ddata->clk_rate_hz);  in axi_pwmgen_round_waveform_fromhw()
130 	wf->duty_length_ns = DIV64_U64_ROUND_UP((u64)wfhw->duty_cycle_cnt * NSEC_PER_SEC,  in axi_pwmgen_round_waveform_fromhw()
131 					    ddata->clk_rate_hz);  in axi_pwmgen_round_waveform_fromhw()
133 	wf->duty_offset_ns = DIV64_U64_ROUND_UP((u64)wfhw->duty_offset_cnt * NSEC_PER_SEC,  in axi_pwmgen_round_waveform_fromhw()
134 					     ddata->clk_rate_hz);  in axi_pwmgen_round_waveform_fromhw()
145 	struct regmap *regmap = ddata->regmap;  in axi_pwmgen_write_waveform()
146 	unsigned int ch = pwm->hwpwm;  in axi_pwmgen_write_waveform()
149 	ret = regmap_write(regmap, AXI_PWMGEN_CHX_PERIOD(ch), wfhw->period_cnt);  in axi_pwmgen_write_waveform()
153 	ret = regmap_write(regmap, AXI_PWMGEN_CHX_DUTY(ch), wfhw->duty_cycle_cnt);  in axi_pwmgen_write_waveform()
157 	ret = regmap_write(regmap, AXI_PWMGEN_CHX_OFFSET(ch), wfhw->duty_offset_cnt);  in axi_pwmgen_write_waveform()
170 	struct regmap *regmap = ddata->regmap;  in axi_pwmgen_read_waveform()
171 	unsigned int ch = pwm->hwpwm;  in axi_pwmgen_read_waveform()
174 	ret = regmap_read(regmap, AXI_PWMGEN_CHX_PERIOD(ch), &wfhw->period_cnt);  in axi_pwmgen_read_waveform()
178 	ret = regmap_read(regmap, AXI_PWMGEN_CHX_DUTY(ch), &wfhw->duty_cycle_cnt);  in axi_pwmgen_read_waveform()
182 	ret = regmap_read(regmap, AXI_PWMGEN_CHX_OFFSET(ch), &wfhw->duty_offset_cnt);  in axi_pwmgen_read_waveform()
186 	if (wfhw->duty_cycle_cnt > wfhw->period_cnt)  in axi_pwmgen_read_waveform()
187 		wfhw->duty_cycle_cnt = wfhw->period_cnt;  in axi_pwmgen_read_waveform()
190 	if (wfhw->duty_offset_cnt >= wfhw->period_cnt) {  in axi_pwmgen_read_waveform()
191 		wfhw->duty_cycle_cnt = 0;  in axi_pwmgen_read_waveform()
192 		wfhw->duty_offset_cnt = 0;  in axi_pwmgen_read_waveform()
216 		return dev_err_probe(dev, -ENODEV,  in axi_pwmgen_setup()
224 	if (ADI_AXI_PCORE_VER_MAJOR(val) != 2) {  in axi_pwmgen_setup()
225 		return dev_err_probe(dev, -ENODEV, "Unsupported peripheral version %u.%u.%u\n",  in axi_pwmgen_setup()
256 	struct device *dev = &pdev->dev;  in axi_pwmgen_probe()
281 	ddata->regmap = regmap;  in axi_pwmgen_probe()
284 	 * Using NULL here instead of "axi" for backwards compatibility. There  in axi_pwmgen_probe()
285 	 * are some dtbs that don't give clock-names and have the "ext" clock  in axi_pwmgen_probe()
290 		return dev_err_probe(dev, PTR_ERR(axi_clk), "failed to get axi clock\n");  in axi_pwmgen_probe()
298 	 * ASYNC_CLK_EN=0. In this case, the AXI clock is also used for the  in axi_pwmgen_probe()
308 	ddata->clk_rate_hz = clk_get_rate(clk);  in axi_pwmgen_probe()
309 	if (!ddata->clk_rate_hz || ddata->clk_rate_hz > NSEC_PER_SEC)  in axi_pwmgen_probe()
310 		return dev_err_probe(dev, -EINVAL,  in axi_pwmgen_probe()
311 				     "Invalid clock rate: %lu\n", ddata->clk_rate_hz);  in axi_pwmgen_probe()
313 	chip->ops = &axi_pwmgen_pwm_ops;  in axi_pwmgen_probe()
314 	chip->atomic = true;  in axi_pwmgen_probe()
324 	{ .compatible = "adi,axi-pwmgen-2.00.a" },
331 		.name = "axi-pwmgen",
341 MODULE_DESCRIPTION("Driver for the Analog Devices AXI PWM generator");