2  * ST SPEAr ADC driver
6  * Licensed under the GPL-2.
16 #include <linux/clk.h>
41 #define SPEAR_ADC_MOD_NAME "spear-adc"
52 	u32 clk;	/* Not avail for 1340 & 1310 */  member
65 	u32 clk;  member
77 	struct clk *clk;  member
87  * Functions to access some SPEAr ADC register. Abstracted into
93 	__raw_writel(val, &st->adc_base_spear6xx->status);  in spear_adc_set_status()
99 	u32 apb_clk = clk_get_rate(st->clk);  in spear_adc_set_clk()
103 	clk_high = count - clk_low;  in spear_adc_set_clk()
104 	st->current_clk = apb_clk / count;  in spear_adc_set_clk()
107 		     &st->adc_base_spear6xx->clk);  in spear_adc_set_clk()
113 	__raw_writel(val, &st->adc_base_spear6xx->ch_ctrl[n]);  in spear_adc_set_ctrl()
118 	if (of_device_is_compatible(st->np, "st,spear600-adc")) {  in spear_adc_get_average()
119 		return __raw_readl(&st->adc_base_spear6xx->average.msb) &  in spear_adc_get_average()
122 		return __raw_readl(&st->adc_base_spear3xx->average) &  in spear_adc_get_average()
129 	if (of_device_is_compatible(st->np, "st,spear600-adc")) {  in spear_adc_set_scanrate()
131 			     &st->adc_base_spear6xx->scan_rate_lo);  in spear_adc_set_scanrate()
133 			     &st->adc_base_spear6xx->scan_rate_hi);  in spear_adc_set_scanrate()
135 		__raw_writel(rate, &st->adc_base_spear3xx->scan_rate);  in spear_adc_set_scanrate()
150 		mutex_lock(&indio_dev->mlock);  in spear_adc_read_raw()
152 		status = SPEAR_ADC_STATUS_CHANNEL_NUM(chan->channel) |  in spear_adc_read_raw()
153 			SPEAR_ADC_STATUS_AVG_SAMPLE(st->avg_samples) |  in spear_adc_read_raw()
156 		if (st->vref_external == 0)  in spear_adc_read_raw()
160 		wait_for_completion(&st->completion); /* set by ISR */  in spear_adc_read_raw()
161 		*val = st->value;  in spear_adc_read_raw()
163 		mutex_unlock(&indio_dev->mlock);  in spear_adc_read_raw()
168 		*val = st->vref_external;  in spear_adc_read_raw()
172 		*val = st->current_clk;  in spear_adc_read_raw()
176 	return -EINVAL;  in spear_adc_read_raw()
189 		return -EINVAL;  in spear_adc_write_raw()
191 	mutex_lock(&indio_dev->mlock);  in spear_adc_write_raw()
196 		ret = -EINVAL;  in spear_adc_write_raw()
203 	mutex_unlock(&indio_dev->mlock);  in spear_adc_write_raw()
232 	st->value = spear_adc_get_average(st);  in spear_adc_isr()
233 	complete(&st->completion);  in spear_adc_isr()
242 	/* Reset ADC core */  in spear_adc_configure()
244 	__raw_writel(0, &st->adc_base_spear6xx->clk);  in spear_adc_configure()
249 	spear_adc_set_clk(st, st->sampling_freq);  in spear_adc_configure()
261 	struct device_node *np = pdev->dev.of_node;  in spear_adc_probe()
262 	struct device *dev = &pdev->dev;  in spear_adc_probe()
266 	int ret = -ENODEV;  in spear_adc_probe()
272 		return -ENOMEM;  in spear_adc_probe()
276 	st->np = np;  in spear_adc_probe()
281 	 * to support multi-arch kernels.  in spear_adc_probe()
284 	st->adc_base_spear6xx = devm_ioremap_resource(&pdev->dev, res);  in spear_adc_probe()
285 	if (IS_ERR(st->adc_base_spear6xx))  in spear_adc_probe()
286 		return PTR_ERR(st->adc_base_spear6xx);  in spear_adc_probe()
288 	st->adc_base_spear3xx =  in spear_adc_probe()
289 		(struct adc_regs_spear3xx __iomem *)st->adc_base_spear6xx;  in spear_adc_probe()
291 	st->clk = devm_clk_get(dev, NULL);  in spear_adc_probe()
292 	if (IS_ERR(st->clk)) {  in spear_adc_probe()
294 		return PTR_ERR(st->clk);  in spear_adc_probe()
297 	ret = clk_prepare_enable(st->clk);  in spear_adc_probe()
306 		ret = -EINVAL;  in spear_adc_probe()
317 	if (of_property_read_u32(np, "sampling-frequency",  in spear_adc_probe()
318 				 &st->sampling_freq)) {  in spear_adc_probe()
319 		dev_err(dev, "sampling-frequency missing in DT\n");  in spear_adc_probe()
320 		ret = -EINVAL;  in spear_adc_probe()
328 	of_property_read_u32(np, "average-samples", &st->avg_samples);  in spear_adc_probe()
334 	of_property_read_u32(np, "vref-external", &st->vref_external);  in spear_adc_probe()
340 	init_completion(&st->completion);  in spear_adc_probe()
342 	indio_dev->name = SPEAR_ADC_MOD_NAME;  in spear_adc_probe()
343 	indio_dev->dev.parent = dev;  in spear_adc_probe()
344 	indio_dev->info = &spear_adc_info;  in spear_adc_probe()
345 	indio_dev->modes = INDIO_DIRECT_MODE;  in spear_adc_probe()
346 	indio_dev->channels = spear_adc_iio_channels;  in spear_adc_probe()
347 	indio_dev->num_channels = ARRAY_SIZE(spear_adc_iio_channels);  in spear_adc_probe()
353 	dev_info(dev, "SPEAR ADC driver loaded, IRQ %d\n", irq);  in spear_adc_probe()
358 	clk_disable_unprepare(st->clk);  in spear_adc_probe()
368 	clk_disable_unprepare(st->clk);  in spear_adc_remove()
375 	{ .compatible = "st,spear600-adc", },
393 MODULE_DESCRIPTION("SPEAr ADC driver");