1 // SPDX-License-Identifier: GPL-2.0
3  * GPADC driver for sunxi platforms (D1, T113-S3 and R329)
18 #include <linux/iio/adc-helpers.h>
21 #define SUN20I_GPADC_DRIVER_NAME	"sun20i-gpadc"
66 	u32 ctrl;  in sun20i_gpadc_adc_read()  local
69 	mutex_lock(&info->lock);  in sun20i_gpadc_adc_read()
71 	reinit_completion(&info->completion);  in sun20i_gpadc_adc_read()
73 	if (info->last_channel != chan->channel) {  in sun20i_gpadc_adc_read()
74 		info->last_channel = chan->channel;  in sun20i_gpadc_adc_read()
77 		writel(SUN20I_GPADC_CS_EN_ADC_CH(chan->channel),  in sun20i_gpadc_adc_read()
78 		       info->regs + SUN20I_GPADC_CS_EN);  in sun20i_gpadc_adc_read()
81 		writel(SUN20I_GPADC_DATA_INTC_CH_DATA_IRQ_EN(chan->channel),  in sun20i_gpadc_adc_read()
82 		       info->regs + SUN20I_GPADC_DATA_INTC);  in sun20i_gpadc_adc_read()
86 	ctrl = readl(info->regs + SUN20I_GPADC_CTRL);  in sun20i_gpadc_adc_read()
87 	ctrl |= FIELD_PREP(SUN20I_GPADC_CTRL_ADC_EN_MASK, 1);  in sun20i_gpadc_adc_read()
88 	writel(ctrl, info->regs + SUN20I_GPADC_CTRL);  in sun20i_gpadc_adc_read()
97 	if (!wait_for_completion_timeout(&info->completion, msecs_to_jiffies(10))) {  in sun20i_gpadc_adc_read()
98 		ret = -ETIMEDOUT;  in sun20i_gpadc_adc_read()
103 	*val = readl(info->regs + SUN20I_GPADC_CH_DATA(chan->channel));  in sun20i_gpadc_adc_read()
106 	mutex_unlock(&info->lock);  in sun20i_gpadc_adc_read()
126 		return -EINVAL;  in sun20i_gpadc_read_raw()
135 	writel(GENMASK(31, 0), info->regs + SUN20I_GPADC_DATA_INTS);  in sun20i_gpadc_irq_handler()
137 	complete(&info->completion);  in sun20i_gpadc_irq_handler()
148 	struct reset_control *rst = data;  in sun20i_gpadc_reset_assert()  local
150 	reset_control_assert(rst);  in sun20i_gpadc_reset_assert()
167 				&sun20i_gpadc_chan_template, -1, &channels);  in sun20i_gpadc_alloc_channels()
171 	indio_dev->channels = channels;  in sun20i_gpadc_alloc_channels()
172 	indio_dev->num_channels = num_channels;  in sun20i_gpadc_alloc_channels()
179 	struct device *dev = &pdev->dev;  in sun20i_gpadc_probe()
182 	struct reset_control *rst;  in sun20i_gpadc_probe()  local
189 		return -ENOMEM;  in sun20i_gpadc_probe()
192 	info->last_channel = -1;  in sun20i_gpadc_probe()
194 	mutex_init(&info->lock);  in sun20i_gpadc_probe()
195 	init_completion(&info->completion);  in sun20i_gpadc_probe()
201 	indio_dev->info = &sun20i_gpadc_iio_info;  in sun20i_gpadc_probe()
202 	indio_dev->name = SUN20I_GPADC_DRIVER_NAME;  in sun20i_gpadc_probe()
204 	info->regs = devm_platform_ioremap_resource(pdev, 0);  in sun20i_gpadc_probe()
205 	if (IS_ERR(info->regs))  in sun20i_gpadc_probe()
206 		return PTR_ERR(info->regs);  in sun20i_gpadc_probe()
212 	rst = devm_reset_control_get_exclusive(dev, NULL);  in sun20i_gpadc_probe()
213 	if (IS_ERR(rst))  in sun20i_gpadc_probe()
214 		return dev_err_probe(dev, PTR_ERR(rst), "failed to get reset control\n");  in sun20i_gpadc_probe()
216 	ret = reset_control_deassert(rst);  in sun20i_gpadc_probe()
220 	ret = devm_add_action_or_reset(dev, sun20i_gpadc_reset_assert, rst);  in sun20i_gpadc_probe()
235 	       info->regs + SUN20I_GPADC_CTRL);  in sun20i_gpadc_probe()
245 	{ .compatible = "allwinner,sun20i-d1-gpadc" },