xref: /OK3568_Linux_fs/kernel/drivers/iio/adc/ti_am335x_adc.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * TI ADC MFD driver
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * Copyright (C) 2012 Texas Instruments Incorporated - https://www.ti.com/
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * This program is free software; you can redistribute it and/or
7*4882a593Smuzhiyun  * modify it under the terms of the GNU General Public License as
8*4882a593Smuzhiyun  * published by the Free Software Foundation version 2.
9*4882a593Smuzhiyun  *
10*4882a593Smuzhiyun  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
11*4882a593Smuzhiyun  * kind, whether express or implied; without even the implied warranty
12*4882a593Smuzhiyun  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13*4882a593Smuzhiyun  * GNU General Public License for more details.
14*4882a593Smuzhiyun  */
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun #include <linux/kernel.h>
17*4882a593Smuzhiyun #include <linux/err.h>
18*4882a593Smuzhiyun #include <linux/module.h>
19*4882a593Smuzhiyun #include <linux/slab.h>
20*4882a593Smuzhiyun #include <linux/interrupt.h>
21*4882a593Smuzhiyun #include <linux/platform_device.h>
22*4882a593Smuzhiyun #include <linux/io.h>
23*4882a593Smuzhiyun #include <linux/iio/iio.h>
24*4882a593Smuzhiyun #include <linux/of.h>
25*4882a593Smuzhiyun #include <linux/of_device.h>
26*4882a593Smuzhiyun #include <linux/iio/machine.h>
27*4882a593Smuzhiyun #include <linux/iio/driver.h>
28*4882a593Smuzhiyun 
29*4882a593Smuzhiyun #include <linux/mfd/ti_am335x_tscadc.h>
30*4882a593Smuzhiyun #include <linux/iio/buffer.h>
31*4882a593Smuzhiyun #include <linux/iio/kfifo_buf.h>
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun #include <linux/dmaengine.h>
34*4882a593Smuzhiyun #include <linux/dma-mapping.h>
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun #define DMA_BUFFER_SIZE		SZ_2K
37*4882a593Smuzhiyun 
38*4882a593Smuzhiyun struct tiadc_dma {
39*4882a593Smuzhiyun 	struct dma_slave_config	conf;
40*4882a593Smuzhiyun 	struct dma_chan		*chan;
41*4882a593Smuzhiyun 	dma_addr_t		addr;
42*4882a593Smuzhiyun 	dma_cookie_t		cookie;
43*4882a593Smuzhiyun 	u8			*buf;
44*4882a593Smuzhiyun 	int			current_period;
45*4882a593Smuzhiyun 	int			period_size;
46*4882a593Smuzhiyun 	u8			fifo_thresh;
47*4882a593Smuzhiyun };
48*4882a593Smuzhiyun 
49*4882a593Smuzhiyun struct tiadc_device {
50*4882a593Smuzhiyun 	struct ti_tscadc_dev *mfd_tscadc;
51*4882a593Smuzhiyun 	struct tiadc_dma dma;
52*4882a593Smuzhiyun 	struct mutex fifo1_lock; /* to protect fifo access */
53*4882a593Smuzhiyun 	int channels;
54*4882a593Smuzhiyun 	int total_ch_enabled;
55*4882a593Smuzhiyun 	u8 channel_line[8];
56*4882a593Smuzhiyun 	u8 channel_step[8];
57*4882a593Smuzhiyun 	int buffer_en_ch_steps;
58*4882a593Smuzhiyun 	u16 data[8];
59*4882a593Smuzhiyun 	u32 open_delay[8], sample_delay[8], step_avg[8];
60*4882a593Smuzhiyun };
61*4882a593Smuzhiyun 
tiadc_readl(struct tiadc_device * adc,unsigned int reg)62*4882a593Smuzhiyun static unsigned int tiadc_readl(struct tiadc_device *adc, unsigned int reg)
63*4882a593Smuzhiyun {
64*4882a593Smuzhiyun 	return readl(adc->mfd_tscadc->tscadc_base + reg);
65*4882a593Smuzhiyun }
66*4882a593Smuzhiyun 
tiadc_writel(struct tiadc_device * adc,unsigned int reg,unsigned int val)67*4882a593Smuzhiyun static void tiadc_writel(struct tiadc_device *adc, unsigned int reg,
68*4882a593Smuzhiyun 					unsigned int val)
69*4882a593Smuzhiyun {
70*4882a593Smuzhiyun 	writel(val, adc->mfd_tscadc->tscadc_base + reg);
71*4882a593Smuzhiyun }
72*4882a593Smuzhiyun 
get_adc_step_mask(struct tiadc_device * adc_dev)73*4882a593Smuzhiyun static u32 get_adc_step_mask(struct tiadc_device *adc_dev)
74*4882a593Smuzhiyun {
75*4882a593Smuzhiyun 	u32 step_en;
76*4882a593Smuzhiyun 
77*4882a593Smuzhiyun 	step_en = ((1 << adc_dev->channels) - 1);
78*4882a593Smuzhiyun 	step_en <<= TOTAL_STEPS - adc_dev->channels + 1;
79*4882a593Smuzhiyun 	return step_en;
80*4882a593Smuzhiyun }
81*4882a593Smuzhiyun 
get_adc_chan_step_mask(struct tiadc_device * adc_dev,struct iio_chan_spec const * chan)82*4882a593Smuzhiyun static u32 get_adc_chan_step_mask(struct tiadc_device *adc_dev,
83*4882a593Smuzhiyun 		struct iio_chan_spec const *chan)
84*4882a593Smuzhiyun {
85*4882a593Smuzhiyun 	int i;
86*4882a593Smuzhiyun 
87*4882a593Smuzhiyun 	for (i = 0; i < ARRAY_SIZE(adc_dev->channel_step); i++) {
88*4882a593Smuzhiyun 		if (chan->channel == adc_dev->channel_line[i]) {
89*4882a593Smuzhiyun 			u32 step;
90*4882a593Smuzhiyun 
91*4882a593Smuzhiyun 			step = adc_dev->channel_step[i];
92*4882a593Smuzhiyun 			/* +1 for the charger */
93*4882a593Smuzhiyun 			return 1 << (step + 1);
94*4882a593Smuzhiyun 		}
95*4882a593Smuzhiyun 	}
96*4882a593Smuzhiyun 	WARN_ON(1);
97*4882a593Smuzhiyun 	return 0;
98*4882a593Smuzhiyun }
99*4882a593Smuzhiyun 
get_adc_step_bit(struct tiadc_device * adc_dev,int chan)100*4882a593Smuzhiyun static u32 get_adc_step_bit(struct tiadc_device *adc_dev, int chan)
101*4882a593Smuzhiyun {
102*4882a593Smuzhiyun 	return 1 << adc_dev->channel_step[chan];
103*4882a593Smuzhiyun }
104*4882a593Smuzhiyun 
tiadc_step_config(struct iio_dev * indio_dev)105*4882a593Smuzhiyun static void tiadc_step_config(struct iio_dev *indio_dev)
106*4882a593Smuzhiyun {
107*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
108*4882a593Smuzhiyun 	struct device *dev = adc_dev->mfd_tscadc->dev;
109*4882a593Smuzhiyun 	unsigned int stepconfig;
110*4882a593Smuzhiyun 	int i, steps = 0;
111*4882a593Smuzhiyun 
112*4882a593Smuzhiyun 	/*
113*4882a593Smuzhiyun 	 * There are 16 configurable steps and 8 analog input
114*4882a593Smuzhiyun 	 * lines available which are shared between Touchscreen and ADC.
115*4882a593Smuzhiyun 	 *
116*4882a593Smuzhiyun 	 * Steps forwards i.e. from 0 towards 16 are used by ADC
117*4882a593Smuzhiyun 	 * depending on number of input lines needed.
118*4882a593Smuzhiyun 	 * Channel would represent which analog input
119*4882a593Smuzhiyun 	 * needs to be given to ADC to digitalize data.
120*4882a593Smuzhiyun 	 */
121*4882a593Smuzhiyun 
122*4882a593Smuzhiyun 
123*4882a593Smuzhiyun 	for (i = 0; i < adc_dev->channels; i++) {
124*4882a593Smuzhiyun 		int chan;
125*4882a593Smuzhiyun 
126*4882a593Smuzhiyun 		chan = adc_dev->channel_line[i];
127*4882a593Smuzhiyun 
128*4882a593Smuzhiyun 		if (adc_dev->step_avg[i] > STEPCONFIG_AVG_16) {
129*4882a593Smuzhiyun 			dev_warn(dev, "chan %d step_avg truncating to %d\n",
130*4882a593Smuzhiyun 				 chan, STEPCONFIG_AVG_16);
131*4882a593Smuzhiyun 			adc_dev->step_avg[i] = STEPCONFIG_AVG_16;
132*4882a593Smuzhiyun 		}
133*4882a593Smuzhiyun 
134*4882a593Smuzhiyun 		if (adc_dev->step_avg[i])
135*4882a593Smuzhiyun 			stepconfig =
136*4882a593Smuzhiyun 			STEPCONFIG_AVG(ffs(adc_dev->step_avg[i]) - 1) |
137*4882a593Smuzhiyun 			STEPCONFIG_FIFO1;
138*4882a593Smuzhiyun 		else
139*4882a593Smuzhiyun 			stepconfig = STEPCONFIG_FIFO1;
140*4882a593Smuzhiyun 
141*4882a593Smuzhiyun 		if (iio_buffer_enabled(indio_dev))
142*4882a593Smuzhiyun 			stepconfig |= STEPCONFIG_MODE_SWCNT;
143*4882a593Smuzhiyun 
144*4882a593Smuzhiyun 		tiadc_writel(adc_dev, REG_STEPCONFIG(steps),
145*4882a593Smuzhiyun 				stepconfig | STEPCONFIG_INP(chan) |
146*4882a593Smuzhiyun 				STEPCONFIG_INM_ADCREFM |
147*4882a593Smuzhiyun 				STEPCONFIG_RFP_VREFP |
148*4882a593Smuzhiyun 				STEPCONFIG_RFM_VREFN);
149*4882a593Smuzhiyun 
150*4882a593Smuzhiyun 		if (adc_dev->open_delay[i] > STEPDELAY_OPEN_MASK) {
151*4882a593Smuzhiyun 			dev_warn(dev, "chan %d open delay truncating to 0x3FFFF\n",
152*4882a593Smuzhiyun 				 chan);
153*4882a593Smuzhiyun 			adc_dev->open_delay[i] = STEPDELAY_OPEN_MASK;
154*4882a593Smuzhiyun 		}
155*4882a593Smuzhiyun 
156*4882a593Smuzhiyun 		if (adc_dev->sample_delay[i] > 0xFF) {
157*4882a593Smuzhiyun 			dev_warn(dev, "chan %d sample delay truncating to 0xFF\n",
158*4882a593Smuzhiyun 				 chan);
159*4882a593Smuzhiyun 			adc_dev->sample_delay[i] = 0xFF;
160*4882a593Smuzhiyun 		}
161*4882a593Smuzhiyun 
162*4882a593Smuzhiyun 		tiadc_writel(adc_dev, REG_STEPDELAY(steps),
163*4882a593Smuzhiyun 				STEPDELAY_OPEN(adc_dev->open_delay[i]) |
164*4882a593Smuzhiyun 				STEPDELAY_SAMPLE(adc_dev->sample_delay[i]));
165*4882a593Smuzhiyun 
166*4882a593Smuzhiyun 		adc_dev->channel_step[i] = steps;
167*4882a593Smuzhiyun 		steps++;
168*4882a593Smuzhiyun 	}
169*4882a593Smuzhiyun }
170*4882a593Smuzhiyun 
tiadc_irq_h(int irq,void * private)171*4882a593Smuzhiyun static irqreturn_t tiadc_irq_h(int irq, void *private)
172*4882a593Smuzhiyun {
173*4882a593Smuzhiyun 	struct iio_dev *indio_dev = private;
174*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
175*4882a593Smuzhiyun 	unsigned int status, config, adc_fsm;
176*4882a593Smuzhiyun 	unsigned short count = 0;
177*4882a593Smuzhiyun 
178*4882a593Smuzhiyun 	status = tiadc_readl(adc_dev, REG_IRQSTATUS);
179*4882a593Smuzhiyun 
180*4882a593Smuzhiyun 	/*
181*4882a593Smuzhiyun 	 * ADC and touchscreen share the IRQ line.
182*4882a593Smuzhiyun 	 * FIFO0 interrupts are used by TSC. Handle FIFO1 IRQs here only
183*4882a593Smuzhiyun 	 */
184*4882a593Smuzhiyun 	if (status & IRQENB_FIFO1OVRRUN) {
185*4882a593Smuzhiyun 		/* FIFO Overrun. Clear flag. Disable/Enable ADC to recover */
186*4882a593Smuzhiyun 		config = tiadc_readl(adc_dev, REG_CTRL);
187*4882a593Smuzhiyun 		config &= ~(CNTRLREG_TSCSSENB);
188*4882a593Smuzhiyun 		tiadc_writel(adc_dev, REG_CTRL, config);
189*4882a593Smuzhiyun 		tiadc_writel(adc_dev, REG_IRQSTATUS, IRQENB_FIFO1OVRRUN
190*4882a593Smuzhiyun 				| IRQENB_FIFO1UNDRFLW | IRQENB_FIFO1THRES);
191*4882a593Smuzhiyun 
192*4882a593Smuzhiyun 		/* wait for idle state.
193*4882a593Smuzhiyun 		 * ADC needs to finish the current conversion
194*4882a593Smuzhiyun 		 * before disabling the module
195*4882a593Smuzhiyun 		 */
196*4882a593Smuzhiyun 		do {
197*4882a593Smuzhiyun 			adc_fsm = tiadc_readl(adc_dev, REG_ADCFSM);
198*4882a593Smuzhiyun 		} while (adc_fsm != 0x10 && count++ < 100);
199*4882a593Smuzhiyun 
200*4882a593Smuzhiyun 		tiadc_writel(adc_dev, REG_CTRL, (config | CNTRLREG_TSCSSENB));
201*4882a593Smuzhiyun 		return IRQ_HANDLED;
202*4882a593Smuzhiyun 	} else if (status & IRQENB_FIFO1THRES) {
203*4882a593Smuzhiyun 		/* Disable irq and wake worker thread */
204*4882a593Smuzhiyun 		tiadc_writel(adc_dev, REG_IRQCLR, IRQENB_FIFO1THRES);
205*4882a593Smuzhiyun 		return IRQ_WAKE_THREAD;
206*4882a593Smuzhiyun 	}
207*4882a593Smuzhiyun 
208*4882a593Smuzhiyun 	return IRQ_NONE;
209*4882a593Smuzhiyun }
210*4882a593Smuzhiyun 
tiadc_worker_h(int irq,void * private)211*4882a593Smuzhiyun static irqreturn_t tiadc_worker_h(int irq, void *private)
212*4882a593Smuzhiyun {
213*4882a593Smuzhiyun 	struct iio_dev *indio_dev = private;
214*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
215*4882a593Smuzhiyun 	int i, k, fifo1count, read;
216*4882a593Smuzhiyun 	u16 *data = adc_dev->data;
217*4882a593Smuzhiyun 
218*4882a593Smuzhiyun 	fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
219*4882a593Smuzhiyun 	for (k = 0; k < fifo1count; k = k + i) {
220*4882a593Smuzhiyun 		for (i = 0; i < (indio_dev->scan_bytes)/2; i++) {
221*4882a593Smuzhiyun 			read = tiadc_readl(adc_dev, REG_FIFO1);
222*4882a593Smuzhiyun 			data[i] = read & FIFOREAD_DATA_MASK;
223*4882a593Smuzhiyun 		}
224*4882a593Smuzhiyun 		iio_push_to_buffers(indio_dev, (u8 *) data);
225*4882a593Smuzhiyun 	}
226*4882a593Smuzhiyun 
227*4882a593Smuzhiyun 	tiadc_writel(adc_dev, REG_IRQSTATUS, IRQENB_FIFO1THRES);
228*4882a593Smuzhiyun 	tiadc_writel(adc_dev, REG_IRQENABLE, IRQENB_FIFO1THRES);
229*4882a593Smuzhiyun 
230*4882a593Smuzhiyun 	return IRQ_HANDLED;
231*4882a593Smuzhiyun }
232*4882a593Smuzhiyun 
tiadc_dma_rx_complete(void * param)233*4882a593Smuzhiyun static void tiadc_dma_rx_complete(void *param)
234*4882a593Smuzhiyun {
235*4882a593Smuzhiyun 	struct iio_dev *indio_dev = param;
236*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
237*4882a593Smuzhiyun 	struct tiadc_dma *dma = &adc_dev->dma;
238*4882a593Smuzhiyun 	u8 *data;
239*4882a593Smuzhiyun 	int i;
240*4882a593Smuzhiyun 
241*4882a593Smuzhiyun 	data = dma->buf + dma->current_period * dma->period_size;
242*4882a593Smuzhiyun 	dma->current_period = 1 - dma->current_period; /* swap the buffer ID */
243*4882a593Smuzhiyun 
244*4882a593Smuzhiyun 	for (i = 0; i < dma->period_size; i += indio_dev->scan_bytes) {
245*4882a593Smuzhiyun 		iio_push_to_buffers(indio_dev, data);
246*4882a593Smuzhiyun 		data += indio_dev->scan_bytes;
247*4882a593Smuzhiyun 	}
248*4882a593Smuzhiyun }
249*4882a593Smuzhiyun 
tiadc_start_dma(struct iio_dev * indio_dev)250*4882a593Smuzhiyun static int tiadc_start_dma(struct iio_dev *indio_dev)
251*4882a593Smuzhiyun {
252*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
253*4882a593Smuzhiyun 	struct tiadc_dma *dma = &adc_dev->dma;
254*4882a593Smuzhiyun 	struct dma_async_tx_descriptor *desc;
255*4882a593Smuzhiyun 
256*4882a593Smuzhiyun 	dma->current_period = 0; /* We start to fill period 0 */
257*4882a593Smuzhiyun 	/*
258*4882a593Smuzhiyun 	 * Make the fifo thresh as the multiple of total number of
259*4882a593Smuzhiyun 	 * channels enabled, so make sure that cyclic DMA period
260*4882a593Smuzhiyun 	 * length is also a multiple of total number of channels
261*4882a593Smuzhiyun 	 * enabled. This ensures that no invalid data is reported
262*4882a593Smuzhiyun 	 * to the stack via iio_push_to_buffers().
263*4882a593Smuzhiyun 	 */
264*4882a593Smuzhiyun 	dma->fifo_thresh = rounddown(FIFO1_THRESHOLD + 1,
265*4882a593Smuzhiyun 				     adc_dev->total_ch_enabled) - 1;
266*4882a593Smuzhiyun 	/* Make sure that period length is multiple of fifo thresh level */
267*4882a593Smuzhiyun 	dma->period_size = rounddown(DMA_BUFFER_SIZE / 2,
268*4882a593Smuzhiyun 				    (dma->fifo_thresh + 1) * sizeof(u16));
269*4882a593Smuzhiyun 
270*4882a593Smuzhiyun 	dma->conf.src_maxburst = dma->fifo_thresh + 1;
271*4882a593Smuzhiyun 	dmaengine_slave_config(dma->chan, &dma->conf);
272*4882a593Smuzhiyun 
273*4882a593Smuzhiyun 	desc = dmaengine_prep_dma_cyclic(dma->chan, dma->addr,
274*4882a593Smuzhiyun 					 dma->period_size * 2,
275*4882a593Smuzhiyun 					 dma->period_size, DMA_DEV_TO_MEM,
276*4882a593Smuzhiyun 					 DMA_PREP_INTERRUPT);
277*4882a593Smuzhiyun 	if (!desc)
278*4882a593Smuzhiyun 		return -EBUSY;
279*4882a593Smuzhiyun 
280*4882a593Smuzhiyun 	desc->callback = tiadc_dma_rx_complete;
281*4882a593Smuzhiyun 	desc->callback_param = indio_dev;
282*4882a593Smuzhiyun 
283*4882a593Smuzhiyun 	dma->cookie = dmaengine_submit(desc);
284*4882a593Smuzhiyun 
285*4882a593Smuzhiyun 	dma_async_issue_pending(dma->chan);
286*4882a593Smuzhiyun 
287*4882a593Smuzhiyun 	tiadc_writel(adc_dev, REG_FIFO1THR, dma->fifo_thresh);
288*4882a593Smuzhiyun 	tiadc_writel(adc_dev, REG_DMA1REQ, dma->fifo_thresh);
289*4882a593Smuzhiyun 	tiadc_writel(adc_dev, REG_DMAENABLE_SET, DMA_FIFO1);
290*4882a593Smuzhiyun 
291*4882a593Smuzhiyun 	return 0;
292*4882a593Smuzhiyun }
293*4882a593Smuzhiyun 
tiadc_buffer_preenable(struct iio_dev * indio_dev)294*4882a593Smuzhiyun static int tiadc_buffer_preenable(struct iio_dev *indio_dev)
295*4882a593Smuzhiyun {
296*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
297*4882a593Smuzhiyun 	int i, fifo1count;
298*4882a593Smuzhiyun 
299*4882a593Smuzhiyun 	tiadc_writel(adc_dev, REG_IRQCLR, (IRQENB_FIFO1THRES |
300*4882a593Smuzhiyun 				IRQENB_FIFO1OVRRUN |
301*4882a593Smuzhiyun 				IRQENB_FIFO1UNDRFLW));
302*4882a593Smuzhiyun 
303*4882a593Smuzhiyun 	/* Flush FIFO. Needed in corner cases in simultaneous tsc/adc use */
304*4882a593Smuzhiyun 	fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
305*4882a593Smuzhiyun 	for (i = 0; i < fifo1count; i++)
306*4882a593Smuzhiyun 		tiadc_readl(adc_dev, REG_FIFO1);
307*4882a593Smuzhiyun 
308*4882a593Smuzhiyun 	return 0;
309*4882a593Smuzhiyun }
310*4882a593Smuzhiyun 
tiadc_buffer_postenable(struct iio_dev * indio_dev)311*4882a593Smuzhiyun static int tiadc_buffer_postenable(struct iio_dev *indio_dev)
312*4882a593Smuzhiyun {
313*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
314*4882a593Smuzhiyun 	struct tiadc_dma *dma = &adc_dev->dma;
315*4882a593Smuzhiyun 	unsigned int irq_enable;
316*4882a593Smuzhiyun 	unsigned int enb = 0;
317*4882a593Smuzhiyun 	u8 bit;
318*4882a593Smuzhiyun 
319*4882a593Smuzhiyun 	tiadc_step_config(indio_dev);
320*4882a593Smuzhiyun 	for_each_set_bit(bit, indio_dev->active_scan_mask, adc_dev->channels) {
321*4882a593Smuzhiyun 		enb |= (get_adc_step_bit(adc_dev, bit) << 1);
322*4882a593Smuzhiyun 		adc_dev->total_ch_enabled++;
323*4882a593Smuzhiyun 	}
324*4882a593Smuzhiyun 	adc_dev->buffer_en_ch_steps = enb;
325*4882a593Smuzhiyun 
326*4882a593Smuzhiyun 	if (dma->chan)
327*4882a593Smuzhiyun 		tiadc_start_dma(indio_dev);
328*4882a593Smuzhiyun 
329*4882a593Smuzhiyun 	am335x_tsc_se_set_cache(adc_dev->mfd_tscadc, enb);
330*4882a593Smuzhiyun 
331*4882a593Smuzhiyun 	tiadc_writel(adc_dev,  REG_IRQSTATUS, IRQENB_FIFO1THRES
332*4882a593Smuzhiyun 				| IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW);
333*4882a593Smuzhiyun 
334*4882a593Smuzhiyun 	irq_enable = IRQENB_FIFO1OVRRUN;
335*4882a593Smuzhiyun 	if (!dma->chan)
336*4882a593Smuzhiyun 		irq_enable |= IRQENB_FIFO1THRES;
337*4882a593Smuzhiyun 	tiadc_writel(adc_dev,  REG_IRQENABLE, irq_enable);
338*4882a593Smuzhiyun 
339*4882a593Smuzhiyun 	return 0;
340*4882a593Smuzhiyun }
341*4882a593Smuzhiyun 
tiadc_buffer_predisable(struct iio_dev * indio_dev)342*4882a593Smuzhiyun static int tiadc_buffer_predisable(struct iio_dev *indio_dev)
343*4882a593Smuzhiyun {
344*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
345*4882a593Smuzhiyun 	struct tiadc_dma *dma = &adc_dev->dma;
346*4882a593Smuzhiyun 	int fifo1count, i;
347*4882a593Smuzhiyun 
348*4882a593Smuzhiyun 	tiadc_writel(adc_dev, REG_IRQCLR, (IRQENB_FIFO1THRES |
349*4882a593Smuzhiyun 				IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW));
350*4882a593Smuzhiyun 	am335x_tsc_se_clr(adc_dev->mfd_tscadc, adc_dev->buffer_en_ch_steps);
351*4882a593Smuzhiyun 	adc_dev->buffer_en_ch_steps = 0;
352*4882a593Smuzhiyun 	adc_dev->total_ch_enabled = 0;
353*4882a593Smuzhiyun 	if (dma->chan) {
354*4882a593Smuzhiyun 		tiadc_writel(adc_dev, REG_DMAENABLE_CLEAR, 0x2);
355*4882a593Smuzhiyun 		dmaengine_terminate_async(dma->chan);
356*4882a593Smuzhiyun 	}
357*4882a593Smuzhiyun 
358*4882a593Smuzhiyun 	/* Flush FIFO of leftover data in the time it takes to disable adc */
359*4882a593Smuzhiyun 	fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
360*4882a593Smuzhiyun 	for (i = 0; i < fifo1count; i++)
361*4882a593Smuzhiyun 		tiadc_readl(adc_dev, REG_FIFO1);
362*4882a593Smuzhiyun 
363*4882a593Smuzhiyun 	return 0;
364*4882a593Smuzhiyun }
365*4882a593Smuzhiyun 
tiadc_buffer_postdisable(struct iio_dev * indio_dev)366*4882a593Smuzhiyun static int tiadc_buffer_postdisable(struct iio_dev *indio_dev)
367*4882a593Smuzhiyun {
368*4882a593Smuzhiyun 	tiadc_step_config(indio_dev);
369*4882a593Smuzhiyun 
370*4882a593Smuzhiyun 	return 0;
371*4882a593Smuzhiyun }
372*4882a593Smuzhiyun 
373*4882a593Smuzhiyun static const struct iio_buffer_setup_ops tiadc_buffer_setup_ops = {
374*4882a593Smuzhiyun 	.preenable = &tiadc_buffer_preenable,
375*4882a593Smuzhiyun 	.postenable = &tiadc_buffer_postenable,
376*4882a593Smuzhiyun 	.predisable = &tiadc_buffer_predisable,
377*4882a593Smuzhiyun 	.postdisable = &tiadc_buffer_postdisable,
378*4882a593Smuzhiyun };
379*4882a593Smuzhiyun 
tiadc_iio_buffered_hardware_setup(struct device * dev,struct iio_dev * indio_dev,irqreturn_t (* pollfunc_bh)(int irq,void * p),irqreturn_t (* pollfunc_th)(int irq,void * p),int irq,unsigned long flags,const struct iio_buffer_setup_ops * setup_ops)380*4882a593Smuzhiyun static int tiadc_iio_buffered_hardware_setup(struct device *dev,
381*4882a593Smuzhiyun 	struct iio_dev *indio_dev,
382*4882a593Smuzhiyun 	irqreturn_t (*pollfunc_bh)(int irq, void *p),
383*4882a593Smuzhiyun 	irqreturn_t (*pollfunc_th)(int irq, void *p),
384*4882a593Smuzhiyun 	int irq,
385*4882a593Smuzhiyun 	unsigned long flags,
386*4882a593Smuzhiyun 	const struct iio_buffer_setup_ops *setup_ops)
387*4882a593Smuzhiyun {
388*4882a593Smuzhiyun 	struct iio_buffer *buffer;
389*4882a593Smuzhiyun 	int ret;
390*4882a593Smuzhiyun 
391*4882a593Smuzhiyun 	buffer = devm_iio_kfifo_allocate(dev);
392*4882a593Smuzhiyun 	if (!buffer)
393*4882a593Smuzhiyun 		return -ENOMEM;
394*4882a593Smuzhiyun 
395*4882a593Smuzhiyun 	iio_device_attach_buffer(indio_dev, buffer);
396*4882a593Smuzhiyun 
397*4882a593Smuzhiyun 	ret = devm_request_threaded_irq(dev, irq, pollfunc_th, pollfunc_bh,
398*4882a593Smuzhiyun 				flags, indio_dev->name, indio_dev);
399*4882a593Smuzhiyun 	if (ret)
400*4882a593Smuzhiyun 		return ret;
401*4882a593Smuzhiyun 
402*4882a593Smuzhiyun 	indio_dev->setup_ops = setup_ops;
403*4882a593Smuzhiyun 	indio_dev->modes |= INDIO_BUFFER_SOFTWARE;
404*4882a593Smuzhiyun 
405*4882a593Smuzhiyun 	return 0;
406*4882a593Smuzhiyun }
407*4882a593Smuzhiyun 
408*4882a593Smuzhiyun static const char * const chan_name_ain[] = {
409*4882a593Smuzhiyun 	"AIN0",
410*4882a593Smuzhiyun 	"AIN1",
411*4882a593Smuzhiyun 	"AIN2",
412*4882a593Smuzhiyun 	"AIN3",
413*4882a593Smuzhiyun 	"AIN4",
414*4882a593Smuzhiyun 	"AIN5",
415*4882a593Smuzhiyun 	"AIN6",
416*4882a593Smuzhiyun 	"AIN7",
417*4882a593Smuzhiyun };
418*4882a593Smuzhiyun 
tiadc_channel_init(struct device * dev,struct iio_dev * indio_dev,int channels)419*4882a593Smuzhiyun static int tiadc_channel_init(struct device *dev, struct iio_dev *indio_dev,
420*4882a593Smuzhiyun 			      int channels)
421*4882a593Smuzhiyun {
422*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
423*4882a593Smuzhiyun 	struct iio_chan_spec *chan_array;
424*4882a593Smuzhiyun 	struct iio_chan_spec *chan;
425*4882a593Smuzhiyun 	int i;
426*4882a593Smuzhiyun 
427*4882a593Smuzhiyun 	indio_dev->num_channels = channels;
428*4882a593Smuzhiyun 	chan_array = devm_kcalloc(dev, channels, sizeof(*chan_array),
429*4882a593Smuzhiyun 				  GFP_KERNEL);
430*4882a593Smuzhiyun 	if (chan_array == NULL)
431*4882a593Smuzhiyun 		return -ENOMEM;
432*4882a593Smuzhiyun 
433*4882a593Smuzhiyun 	chan = chan_array;
434*4882a593Smuzhiyun 	for (i = 0; i < channels; i++, chan++) {
435*4882a593Smuzhiyun 
436*4882a593Smuzhiyun 		chan->type = IIO_VOLTAGE;
437*4882a593Smuzhiyun 		chan->indexed = 1;
438*4882a593Smuzhiyun 		chan->channel = adc_dev->channel_line[i];
439*4882a593Smuzhiyun 		chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
440*4882a593Smuzhiyun 		chan->datasheet_name = chan_name_ain[chan->channel];
441*4882a593Smuzhiyun 		chan->scan_index = i;
442*4882a593Smuzhiyun 		chan->scan_type.sign = 'u';
443*4882a593Smuzhiyun 		chan->scan_type.realbits = 12;
444*4882a593Smuzhiyun 		chan->scan_type.storagebits = 16;
445*4882a593Smuzhiyun 	}
446*4882a593Smuzhiyun 
447*4882a593Smuzhiyun 	indio_dev->channels = chan_array;
448*4882a593Smuzhiyun 
449*4882a593Smuzhiyun 	return 0;
450*4882a593Smuzhiyun }
451*4882a593Smuzhiyun 
tiadc_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)452*4882a593Smuzhiyun static int tiadc_read_raw(struct iio_dev *indio_dev,
453*4882a593Smuzhiyun 		struct iio_chan_spec const *chan,
454*4882a593Smuzhiyun 		int *val, int *val2, long mask)
455*4882a593Smuzhiyun {
456*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
457*4882a593Smuzhiyun 	int ret = IIO_VAL_INT;
458*4882a593Smuzhiyun 	int i, map_val;
459*4882a593Smuzhiyun 	unsigned int fifo1count, read, stepid;
460*4882a593Smuzhiyun 	bool found = false;
461*4882a593Smuzhiyun 	u32 step_en;
462*4882a593Smuzhiyun 	unsigned long timeout;
463*4882a593Smuzhiyun 
464*4882a593Smuzhiyun 	if (iio_buffer_enabled(indio_dev))
465*4882a593Smuzhiyun 		return -EBUSY;
466*4882a593Smuzhiyun 
467*4882a593Smuzhiyun 	step_en = get_adc_chan_step_mask(adc_dev, chan);
468*4882a593Smuzhiyun 	if (!step_en)
469*4882a593Smuzhiyun 		return -EINVAL;
470*4882a593Smuzhiyun 
471*4882a593Smuzhiyun 	mutex_lock(&adc_dev->fifo1_lock);
472*4882a593Smuzhiyun 	fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
473*4882a593Smuzhiyun 	while (fifo1count--)
474*4882a593Smuzhiyun 		tiadc_readl(adc_dev, REG_FIFO1);
475*4882a593Smuzhiyun 
476*4882a593Smuzhiyun 	am335x_tsc_se_set_once(adc_dev->mfd_tscadc, step_en);
477*4882a593Smuzhiyun 
478*4882a593Smuzhiyun 	timeout = jiffies + msecs_to_jiffies
479*4882a593Smuzhiyun 				(IDLE_TIMEOUT * adc_dev->channels);
480*4882a593Smuzhiyun 	/* Wait for Fifo threshold interrupt */
481*4882a593Smuzhiyun 	while (1) {
482*4882a593Smuzhiyun 		fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
483*4882a593Smuzhiyun 		if (fifo1count)
484*4882a593Smuzhiyun 			break;
485*4882a593Smuzhiyun 
486*4882a593Smuzhiyun 		if (time_after(jiffies, timeout)) {
487*4882a593Smuzhiyun 			am335x_tsc_se_adc_done(adc_dev->mfd_tscadc);
488*4882a593Smuzhiyun 			ret = -EAGAIN;
489*4882a593Smuzhiyun 			goto err_unlock;
490*4882a593Smuzhiyun 		}
491*4882a593Smuzhiyun 	}
492*4882a593Smuzhiyun 	map_val = adc_dev->channel_step[chan->scan_index];
493*4882a593Smuzhiyun 
494*4882a593Smuzhiyun 	/*
495*4882a593Smuzhiyun 	 * We check the complete FIFO. We programmed just one entry but in case
496*4882a593Smuzhiyun 	 * something went wrong we left empty handed (-EAGAIN previously) and
497*4882a593Smuzhiyun 	 * then the value apeared somehow in the FIFO we would have two entries.
498*4882a593Smuzhiyun 	 * Therefore we read every item and keep only the latest version of the
499*4882a593Smuzhiyun 	 * requested channel.
500*4882a593Smuzhiyun 	 */
501*4882a593Smuzhiyun 	for (i = 0; i < fifo1count; i++) {
502*4882a593Smuzhiyun 		read = tiadc_readl(adc_dev, REG_FIFO1);
503*4882a593Smuzhiyun 		stepid = read & FIFOREAD_CHNLID_MASK;
504*4882a593Smuzhiyun 		stepid = stepid >> 0x10;
505*4882a593Smuzhiyun 
506*4882a593Smuzhiyun 		if (stepid == map_val) {
507*4882a593Smuzhiyun 			read = read & FIFOREAD_DATA_MASK;
508*4882a593Smuzhiyun 			found = true;
509*4882a593Smuzhiyun 			*val = (u16) read;
510*4882a593Smuzhiyun 		}
511*4882a593Smuzhiyun 	}
512*4882a593Smuzhiyun 	am335x_tsc_se_adc_done(adc_dev->mfd_tscadc);
513*4882a593Smuzhiyun 
514*4882a593Smuzhiyun 	if (!found)
515*4882a593Smuzhiyun 		ret =  -EBUSY;
516*4882a593Smuzhiyun 
517*4882a593Smuzhiyun err_unlock:
518*4882a593Smuzhiyun 	mutex_unlock(&adc_dev->fifo1_lock);
519*4882a593Smuzhiyun 	return ret;
520*4882a593Smuzhiyun }
521*4882a593Smuzhiyun 
522*4882a593Smuzhiyun static const struct iio_info tiadc_info = {
523*4882a593Smuzhiyun 	.read_raw = &tiadc_read_raw,
524*4882a593Smuzhiyun };
525*4882a593Smuzhiyun 
tiadc_request_dma(struct platform_device * pdev,struct tiadc_device * adc_dev)526*4882a593Smuzhiyun static int tiadc_request_dma(struct platform_device *pdev,
527*4882a593Smuzhiyun 			     struct tiadc_device *adc_dev)
528*4882a593Smuzhiyun {
529*4882a593Smuzhiyun 	struct tiadc_dma	*dma = &adc_dev->dma;
530*4882a593Smuzhiyun 	dma_cap_mask_t		mask;
531*4882a593Smuzhiyun 
532*4882a593Smuzhiyun 	/* Default slave configuration parameters */
533*4882a593Smuzhiyun 	dma->conf.direction = DMA_DEV_TO_MEM;
534*4882a593Smuzhiyun 	dma->conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
535*4882a593Smuzhiyun 	dma->conf.src_addr = adc_dev->mfd_tscadc->tscadc_phys_base + REG_FIFO1;
536*4882a593Smuzhiyun 
537*4882a593Smuzhiyun 	dma_cap_zero(mask);
538*4882a593Smuzhiyun 	dma_cap_set(DMA_CYCLIC, mask);
539*4882a593Smuzhiyun 
540*4882a593Smuzhiyun 	/* Get a channel for RX */
541*4882a593Smuzhiyun 	dma->chan = dma_request_chan(adc_dev->mfd_tscadc->dev, "fifo1");
542*4882a593Smuzhiyun 	if (IS_ERR(dma->chan)) {
543*4882a593Smuzhiyun 		int ret = PTR_ERR(dma->chan);
544*4882a593Smuzhiyun 
545*4882a593Smuzhiyun 		dma->chan = NULL;
546*4882a593Smuzhiyun 		return ret;
547*4882a593Smuzhiyun 	}
548*4882a593Smuzhiyun 
549*4882a593Smuzhiyun 	/* RX buffer */
550*4882a593Smuzhiyun 	dma->buf = dma_alloc_coherent(dma->chan->device->dev, DMA_BUFFER_SIZE,
551*4882a593Smuzhiyun 				      &dma->addr, GFP_KERNEL);
552*4882a593Smuzhiyun 	if (!dma->buf)
553*4882a593Smuzhiyun 		goto err;
554*4882a593Smuzhiyun 
555*4882a593Smuzhiyun 	return 0;
556*4882a593Smuzhiyun err:
557*4882a593Smuzhiyun 	dma_release_channel(dma->chan);
558*4882a593Smuzhiyun 	return -ENOMEM;
559*4882a593Smuzhiyun }
560*4882a593Smuzhiyun 
tiadc_parse_dt(struct platform_device * pdev,struct tiadc_device * adc_dev)561*4882a593Smuzhiyun static int tiadc_parse_dt(struct platform_device *pdev,
562*4882a593Smuzhiyun 			  struct tiadc_device *adc_dev)
563*4882a593Smuzhiyun {
564*4882a593Smuzhiyun 	struct device_node *node = pdev->dev.of_node;
565*4882a593Smuzhiyun 	struct property *prop;
566*4882a593Smuzhiyun 	const __be32 *cur;
567*4882a593Smuzhiyun 	int channels = 0;
568*4882a593Smuzhiyun 	u32 val;
569*4882a593Smuzhiyun 
570*4882a593Smuzhiyun 	of_property_for_each_u32(node, "ti,adc-channels", prop, cur, val) {
571*4882a593Smuzhiyun 		adc_dev->channel_line[channels] = val;
572*4882a593Smuzhiyun 
573*4882a593Smuzhiyun 		/* Set Default values for optional DT parameters */
574*4882a593Smuzhiyun 		adc_dev->open_delay[channels] = STEPCONFIG_OPENDLY;
575*4882a593Smuzhiyun 		adc_dev->sample_delay[channels] = STEPCONFIG_SAMPLEDLY;
576*4882a593Smuzhiyun 		adc_dev->step_avg[channels] = 16;
577*4882a593Smuzhiyun 
578*4882a593Smuzhiyun 		channels++;
579*4882a593Smuzhiyun 	}
580*4882a593Smuzhiyun 
581*4882a593Smuzhiyun 	of_property_read_u32_array(node, "ti,chan-step-avg",
582*4882a593Smuzhiyun 				   adc_dev->step_avg, channels);
583*4882a593Smuzhiyun 	of_property_read_u32_array(node, "ti,chan-step-opendelay",
584*4882a593Smuzhiyun 				   adc_dev->open_delay, channels);
585*4882a593Smuzhiyun 	of_property_read_u32_array(node, "ti,chan-step-sampledelay",
586*4882a593Smuzhiyun 				   adc_dev->sample_delay, channels);
587*4882a593Smuzhiyun 
588*4882a593Smuzhiyun 	adc_dev->channels = channels;
589*4882a593Smuzhiyun 	return 0;
590*4882a593Smuzhiyun }
591*4882a593Smuzhiyun 
tiadc_probe(struct platform_device * pdev)592*4882a593Smuzhiyun static int tiadc_probe(struct platform_device *pdev)
593*4882a593Smuzhiyun {
594*4882a593Smuzhiyun 	struct iio_dev		*indio_dev;
595*4882a593Smuzhiyun 	struct tiadc_device	*adc_dev;
596*4882a593Smuzhiyun 	struct device_node	*node = pdev->dev.of_node;
597*4882a593Smuzhiyun 	int			err;
598*4882a593Smuzhiyun 
599*4882a593Smuzhiyun 	if (!node) {
600*4882a593Smuzhiyun 		dev_err(&pdev->dev, "Could not find valid DT data.\n");
601*4882a593Smuzhiyun 		return -EINVAL;
602*4882a593Smuzhiyun 	}
603*4882a593Smuzhiyun 
604*4882a593Smuzhiyun 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc_dev));
605*4882a593Smuzhiyun 	if (indio_dev == NULL) {
606*4882a593Smuzhiyun 		dev_err(&pdev->dev, "failed to allocate iio device\n");
607*4882a593Smuzhiyun 		return -ENOMEM;
608*4882a593Smuzhiyun 	}
609*4882a593Smuzhiyun 	adc_dev = iio_priv(indio_dev);
610*4882a593Smuzhiyun 
611*4882a593Smuzhiyun 	adc_dev->mfd_tscadc = ti_tscadc_dev_get(pdev);
612*4882a593Smuzhiyun 	tiadc_parse_dt(pdev, adc_dev);
613*4882a593Smuzhiyun 
614*4882a593Smuzhiyun 	indio_dev->name = dev_name(&pdev->dev);
615*4882a593Smuzhiyun 	indio_dev->modes = INDIO_DIRECT_MODE;
616*4882a593Smuzhiyun 	indio_dev->info = &tiadc_info;
617*4882a593Smuzhiyun 
618*4882a593Smuzhiyun 	tiadc_step_config(indio_dev);
619*4882a593Smuzhiyun 	tiadc_writel(adc_dev, REG_FIFO1THR, FIFO1_THRESHOLD);
620*4882a593Smuzhiyun 	mutex_init(&adc_dev->fifo1_lock);
621*4882a593Smuzhiyun 
622*4882a593Smuzhiyun 	err = tiadc_channel_init(&pdev->dev, indio_dev, adc_dev->channels);
623*4882a593Smuzhiyun 	if (err < 0)
624*4882a593Smuzhiyun 		return err;
625*4882a593Smuzhiyun 
626*4882a593Smuzhiyun 	err = tiadc_iio_buffered_hardware_setup(&pdev->dev, indio_dev,
627*4882a593Smuzhiyun 		&tiadc_worker_h,
628*4882a593Smuzhiyun 		&tiadc_irq_h,
629*4882a593Smuzhiyun 		adc_dev->mfd_tscadc->irq,
630*4882a593Smuzhiyun 		IRQF_SHARED,
631*4882a593Smuzhiyun 		&tiadc_buffer_setup_ops);
632*4882a593Smuzhiyun 
633*4882a593Smuzhiyun 	if (err)
634*4882a593Smuzhiyun 		goto err_free_channels;
635*4882a593Smuzhiyun 
636*4882a593Smuzhiyun 	err = iio_device_register(indio_dev);
637*4882a593Smuzhiyun 	if (err)
638*4882a593Smuzhiyun 		goto err_buffer_unregister;
639*4882a593Smuzhiyun 
640*4882a593Smuzhiyun 	platform_set_drvdata(pdev, indio_dev);
641*4882a593Smuzhiyun 
642*4882a593Smuzhiyun 	err = tiadc_request_dma(pdev, adc_dev);
643*4882a593Smuzhiyun 	if (err && err == -EPROBE_DEFER)
644*4882a593Smuzhiyun 		goto err_dma;
645*4882a593Smuzhiyun 
646*4882a593Smuzhiyun 	return 0;
647*4882a593Smuzhiyun 
648*4882a593Smuzhiyun err_dma:
649*4882a593Smuzhiyun 	iio_device_unregister(indio_dev);
650*4882a593Smuzhiyun err_buffer_unregister:
651*4882a593Smuzhiyun err_free_channels:
652*4882a593Smuzhiyun 	return err;
653*4882a593Smuzhiyun }
654*4882a593Smuzhiyun 
tiadc_remove(struct platform_device * pdev)655*4882a593Smuzhiyun static int tiadc_remove(struct platform_device *pdev)
656*4882a593Smuzhiyun {
657*4882a593Smuzhiyun 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
658*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
659*4882a593Smuzhiyun 	struct tiadc_dma *dma = &adc_dev->dma;
660*4882a593Smuzhiyun 	u32 step_en;
661*4882a593Smuzhiyun 
662*4882a593Smuzhiyun 	if (dma->chan) {
663*4882a593Smuzhiyun 		dma_free_coherent(dma->chan->device->dev, DMA_BUFFER_SIZE,
664*4882a593Smuzhiyun 				  dma->buf, dma->addr);
665*4882a593Smuzhiyun 		dma_release_channel(dma->chan);
666*4882a593Smuzhiyun 	}
667*4882a593Smuzhiyun 	iio_device_unregister(indio_dev);
668*4882a593Smuzhiyun 
669*4882a593Smuzhiyun 	step_en = get_adc_step_mask(adc_dev);
670*4882a593Smuzhiyun 	am335x_tsc_se_clr(adc_dev->mfd_tscadc, step_en);
671*4882a593Smuzhiyun 
672*4882a593Smuzhiyun 	return 0;
673*4882a593Smuzhiyun }
674*4882a593Smuzhiyun 
tiadc_suspend(struct device * dev)675*4882a593Smuzhiyun static int __maybe_unused tiadc_suspend(struct device *dev)
676*4882a593Smuzhiyun {
677*4882a593Smuzhiyun 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
678*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
679*4882a593Smuzhiyun 	unsigned int idle;
680*4882a593Smuzhiyun 
681*4882a593Smuzhiyun 	idle = tiadc_readl(adc_dev, REG_CTRL);
682*4882a593Smuzhiyun 	idle &= ~(CNTRLREG_TSCSSENB);
683*4882a593Smuzhiyun 	tiadc_writel(adc_dev, REG_CTRL, (idle |
684*4882a593Smuzhiyun 			CNTRLREG_POWERDOWN));
685*4882a593Smuzhiyun 
686*4882a593Smuzhiyun 	return 0;
687*4882a593Smuzhiyun }
688*4882a593Smuzhiyun 
tiadc_resume(struct device * dev)689*4882a593Smuzhiyun static int __maybe_unused tiadc_resume(struct device *dev)
690*4882a593Smuzhiyun {
691*4882a593Smuzhiyun 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
692*4882a593Smuzhiyun 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
693*4882a593Smuzhiyun 	unsigned int restore;
694*4882a593Smuzhiyun 
695*4882a593Smuzhiyun 	/* Make sure ADC is powered up */
696*4882a593Smuzhiyun 	restore = tiadc_readl(adc_dev, REG_CTRL);
697*4882a593Smuzhiyun 	restore &= ~(CNTRLREG_POWERDOWN);
698*4882a593Smuzhiyun 	tiadc_writel(adc_dev, REG_CTRL, restore);
699*4882a593Smuzhiyun 
700*4882a593Smuzhiyun 	tiadc_step_config(indio_dev);
701*4882a593Smuzhiyun 	am335x_tsc_se_set_cache(adc_dev->mfd_tscadc,
702*4882a593Smuzhiyun 			adc_dev->buffer_en_ch_steps);
703*4882a593Smuzhiyun 	return 0;
704*4882a593Smuzhiyun }
705*4882a593Smuzhiyun 
706*4882a593Smuzhiyun static SIMPLE_DEV_PM_OPS(tiadc_pm_ops, tiadc_suspend, tiadc_resume);
707*4882a593Smuzhiyun 
708*4882a593Smuzhiyun static const struct of_device_id ti_adc_dt_ids[] = {
709*4882a593Smuzhiyun 	{ .compatible = "ti,am3359-adc", },
710*4882a593Smuzhiyun 	{ }
711*4882a593Smuzhiyun };
712*4882a593Smuzhiyun MODULE_DEVICE_TABLE(of, ti_adc_dt_ids);
713*4882a593Smuzhiyun 
714*4882a593Smuzhiyun static struct platform_driver tiadc_driver = {
715*4882a593Smuzhiyun 	.driver = {
716*4882a593Smuzhiyun 		.name   = "TI-am335x-adc",
717*4882a593Smuzhiyun 		.pm	= &tiadc_pm_ops,
718*4882a593Smuzhiyun 		.of_match_table = ti_adc_dt_ids,
719*4882a593Smuzhiyun 	},
720*4882a593Smuzhiyun 	.probe	= tiadc_probe,
721*4882a593Smuzhiyun 	.remove	= tiadc_remove,
722*4882a593Smuzhiyun };
723*4882a593Smuzhiyun module_platform_driver(tiadc_driver);
724*4882a593Smuzhiyun 
725*4882a593Smuzhiyun MODULE_DESCRIPTION("TI ADC controller driver");
726*4882a593Smuzhiyun MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
727*4882a593Smuzhiyun MODULE_LICENSE("GPL");
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