1 // SPDX-License-Identifier: GPL-2.0+
3  *  lpc32xx_adc.c - Support for ADC in LPC32XX
5  *  3-channel, 10-bit ADC
10 #include <linux/clk.h>
46 #define LPC32XXAD_NAME "lpc32xx-adc"
50 	struct clk *clk;  member
70 		mutex_lock(&st->lock);  in lpc32xx_read_raw()
71 		ret = clk_prepare_enable(st->clk);  in lpc32xx_read_raw()
73 			mutex_unlock(&st->lock);  in lpc32xx_read_raw()
77 		__raw_writel(LPC32XXAD_INTERNAL | (chan->address) |  in lpc32xx_read_raw()
79 			     LPC32XXAD_SELECT(st->adc_base));  in lpc32xx_read_raw()
82 			     LPC32XXAD_CTRL(st->adc_base));  in lpc32xx_read_raw()
83 		wait_for_completion(&st->completion); /* set by ISR */  in lpc32xx_read_raw()
84 		clk_disable_unprepare(st->clk);  in lpc32xx_read_raw()
85 		*val = st->value;  in lpc32xx_read_raw()
86 		mutex_unlock(&st->lock);  in lpc32xx_read_raw()
91 		*val = regulator_get_voltage(st->vref) / 1000;  in lpc32xx_read_raw()
96 		return -EINVAL;  in lpc32xx_read_raw()
138 	st->value = __raw_readl(LPC32XXAD_VALUE(st->adc_base)) &  in lpc32xx_adc_isr()
140 	complete(&st->completion);  in lpc32xx_adc_isr()
149 	int retval = -ENODEV;  in lpc32xx_adc_probe()
155 		dev_err(&pdev->dev, "failed to get platform I/O memory\n");  in lpc32xx_adc_probe()
156 		return -ENXIO;  in lpc32xx_adc_probe()
159 	iodev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));  in lpc32xx_adc_probe()
161 		return -ENOMEM;  in lpc32xx_adc_probe()
165 	st->adc_base = devm_ioremap(&pdev->dev, res->start,  in lpc32xx_adc_probe()
167 	if (!st->adc_base) {  in lpc32xx_adc_probe()
168 		dev_err(&pdev->dev, "failed mapping memory\n");  in lpc32xx_adc_probe()
169 		return -EBUSY;  in lpc32xx_adc_probe()
172 	st->clk = devm_clk_get(&pdev->dev, NULL);  in lpc32xx_adc_probe()
173 	if (IS_ERR(st->clk)) {  in lpc32xx_adc_probe()
174 		dev_err(&pdev->dev, "failed getting clock\n");  in lpc32xx_adc_probe()
175 		return PTR_ERR(st->clk);  in lpc32xx_adc_probe()
182 	retval = devm_request_irq(&pdev->dev, irq, lpc32xx_adc_isr, 0,  in lpc32xx_adc_probe()
185 		dev_err(&pdev->dev, "failed requesting interrupt\n");  in lpc32xx_adc_probe()
189 	st->vref = devm_regulator_get(&pdev->dev, "vref");  in lpc32xx_adc_probe()
190 	if (IS_ERR(st->vref)) {  in lpc32xx_adc_probe()
191 		iodev->channels = lpc32xx_adc_iio_channels;  in lpc32xx_adc_probe()
192 		dev_info(&pdev->dev,  in lpc32xx_adc_probe()
195 		iodev->channels = lpc32xx_adc_iio_scale_channels;  in lpc32xx_adc_probe()
200 	init_completion(&st->completion);  in lpc32xx_adc_probe()
202 	iodev->name = LPC32XXAD_NAME;  in lpc32xx_adc_probe()
203 	iodev->info = &lpc32xx_adc_iio_info;  in lpc32xx_adc_probe()
204 	iodev->modes = INDIO_DIRECT_MODE;  in lpc32xx_adc_probe()
205 	iodev->num_channels = ARRAY_SIZE(lpc32xx_adc_iio_channels);  in lpc32xx_adc_probe()
207 	mutex_init(&st->lock);  in lpc32xx_adc_probe()
209 	retval = devm_iio_device_register(&pdev->dev, iodev);  in lpc32xx_adc_probe()
213 	dev_info(&pdev->dev, "LPC32XX ADC driver loaded, IRQ %d\n", irq);  in lpc32xx_adc_probe()
219 	{ .compatible = "nxp,lpc3220-adc" },