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[mirror_ubuntu-zesty-kernel.git] / drivers / mfd / ti_am335x_tscadc.c
CommitLineData
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1/*
2 * TI Touch Screen / ADC MFD driver
3 *
4 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation version 2.
9 *
10 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
11 * kind, whether express or implied; without even the implied warranty
12 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16#include <linux/module.h>
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17#include <linux/slab.h>
18#include <linux/err.h>
19#include <linux/io.h>
20#include <linux/clk.h>
21#include <linux/regmap.h>
22#include <linux/mfd/core.h>
23#include <linux/pm_runtime.h>
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24#include <linux/of.h>
25#include <linux/of_device.h>
7ca6740c 26#include <linux/sched.h>
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27
28#include <linux/mfd/ti_am335x_tscadc.h>
29
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30static const struct regmap_config tscadc_regmap_config = {
31 .name = "ti_tscadc",
32 .reg_bits = 32,
33 .reg_stride = 4,
34 .val_bits = 32,
35};
36
a318b7d0 37void am335x_tsc_se_set_cache(struct ti_tscadc_dev *tscadc, u32 val)
abeccee4 38{
317b2099
SAS
39 unsigned long flags;
40
a318b7d0
AD
41 spin_lock_irqsave(&tscadc->reg_lock, flags);
42 tscadc->reg_se_cache |= val;
43 if (tscadc->adc_waiting)
44 wake_up(&tscadc->reg_se_wait);
45 else if (!tscadc->adc_in_use)
0d3a7cce 46 regmap_write(tscadc->regmap, REG_SE, tscadc->reg_se_cache);
7ca6740c 47
a318b7d0 48 spin_unlock_irqrestore(&tscadc->reg_lock, flags);
abeccee4 49}
7e170c6e
SAS
50EXPORT_SYMBOL_GPL(am335x_tsc_se_set_cache);
51
a318b7d0 52static void am335x_tscadc_need_adc(struct ti_tscadc_dev *tscadc)
7ca6740c
SAS
53{
54 DEFINE_WAIT(wait);
55 u32 reg;
56
0d3a7cce 57 regmap_read(tscadc->regmap, REG_ADCFSM, &reg);
7ca6740c 58 if (reg & SEQ_STATUS) {
a318b7d0
AD
59 tscadc->adc_waiting = true;
60 prepare_to_wait(&tscadc->reg_se_wait, &wait,
7ca6740c 61 TASK_UNINTERRUPTIBLE);
a318b7d0 62 spin_unlock_irq(&tscadc->reg_lock);
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63
64 schedule();
65
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AD
66 spin_lock_irq(&tscadc->reg_lock);
67 finish_wait(&tscadc->reg_se_wait, &wait);
7ca6740c 68
b10848e6
V
69 /*
70 * Sequencer should either be idle or
71 * busy applying the charge step.
72 */
0d3a7cce 73 regmap_read(tscadc->regmap, REG_ADCFSM, &reg);
b10848e6 74 WARN_ON((reg & SEQ_STATUS) && !(reg & CHARGE_STEP));
a318b7d0 75 tscadc->adc_waiting = false;
7ca6740c 76 }
a318b7d0 77 tscadc->adc_in_use = true;
7ca6740c
SAS
78}
79
a318b7d0 80void am335x_tsc_se_set_once(struct ti_tscadc_dev *tscadc, u32 val)
7ca6740c 81{
a318b7d0
AD
82 spin_lock_irq(&tscadc->reg_lock);
83 am335x_tscadc_need_adc(tscadc);
7ca6740c 84
0d3a7cce 85 regmap_write(tscadc->regmap, REG_SE, val);
a318b7d0 86 spin_unlock_irq(&tscadc->reg_lock);
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SAS
87}
88EXPORT_SYMBOL_GPL(am335x_tsc_se_set_once);
89
a318b7d0 90void am335x_tsc_se_adc_done(struct ti_tscadc_dev *tscadc)
7e170c6e
SAS
91{
92 unsigned long flags;
93
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AD
94 spin_lock_irqsave(&tscadc->reg_lock, flags);
95 tscadc->adc_in_use = false;
0d3a7cce 96 regmap_write(tscadc->regmap, REG_SE, tscadc->reg_se_cache);
a318b7d0 97 spin_unlock_irqrestore(&tscadc->reg_lock, flags);
7e170c6e 98}
7ca6740c 99EXPORT_SYMBOL_GPL(am335x_tsc_se_adc_done);
abeccee4 100
a318b7d0 101void am335x_tsc_se_clr(struct ti_tscadc_dev *tscadc, u32 val)
abeccee4 102{
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103 unsigned long flags;
104
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AD
105 spin_lock_irqsave(&tscadc->reg_lock, flags);
106 tscadc->reg_se_cache &= ~val;
0d3a7cce 107 regmap_write(tscadc->regmap, REG_SE, tscadc->reg_se_cache);
a318b7d0 108 spin_unlock_irqrestore(&tscadc->reg_lock, flags);
abeccee4
PR
109}
110EXPORT_SYMBOL_GPL(am335x_tsc_se_clr);
111
a318b7d0 112static void tscadc_idle_config(struct ti_tscadc_dev *tscadc)
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113{
114 unsigned int idleconfig;
115
116 idleconfig = STEPCONFIG_YNN | STEPCONFIG_INM_ADCREFM |
117 STEPCONFIG_INP_ADCREFM | STEPCONFIG_YPN;
118
0d3a7cce 119 regmap_write(tscadc->regmap, REG_IDLECONFIG, idleconfig);
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120}
121
612b95cd 122static int ti_tscadc_probe(struct platform_device *pdev)
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123{
124 struct ti_tscadc_dev *tscadc;
125 struct resource *res;
126 struct clk *clk;
a6543a1c 127 struct device_node *node = pdev->dev.of_node;
2b99bafa 128 struct mfd_cell *cell;
18926ede
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129 struct property *prop;
130 const __be32 *cur;
131 u32 val;
01636eb9 132 int err, ctrl;
e90f8754 133 int clock_rate;
a6543a1c 134 int tsc_wires = 0, adc_channels = 0, total_channels;
18926ede 135 int readouts = 0;
01636eb9 136
9e5775f3
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137 if (!pdev->dev.of_node) {
138 dev_err(&pdev->dev, "Could not find valid DT data.\n");
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139 return -EINVAL;
140 }
141
9e5775f3
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142 node = of_get_child_by_name(pdev->dev.of_node, "tsc");
143 of_property_read_u32(node, "ti,wires", &tsc_wires);
18926ede 144 of_property_read_u32(node, "ti,coordiante-readouts", &readouts);
a6543a1c 145
9e5775f3 146 node = of_get_child_by_name(pdev->dev.of_node, "adc");
18926ede
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147 of_property_for_each_u32(node, "ti,adc-channels", prop, cur, val) {
148 adc_channels++;
149 if (val > 7) {
150 dev_err(&pdev->dev, " PIN numbers are 0..7 (not %d)\n",
151 val);
152 return -EINVAL;
153 }
154 }
5e53a69b 155 total_channels = tsc_wires + adc_channels;
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PR
156 if (total_channels > 8) {
157 dev_err(&pdev->dev, "Number of i/p channels more than 8\n");
158 return -EINVAL;
159 }
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PA
160 if (total_channels == 0) {
161 dev_err(&pdev->dev, "Need atleast one channel.\n");
162 return -EINVAL;
163 }
2b99bafa 164
18926ede
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165 if (readouts * 2 + 2 + adc_channels > 16) {
166 dev_err(&pdev->dev, "Too many step configurations requested\n");
167 return -EINVAL;
168 }
169
01636eb9 170 /* Allocate memory for device */
dea1c703 171 tscadc = devm_kzalloc(&pdev->dev, sizeof(*tscadc), GFP_KERNEL);
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172 if (!tscadc) {
173 dev_err(&pdev->dev, "failed to allocate memory.\n");
174 return -ENOMEM;
175 }
176 tscadc->dev = &pdev->dev;
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PR
177
178 err = platform_get_irq(pdev, 0);
179 if (err < 0) {
180 dev_err(&pdev->dev, "no irq ID is specified.\n");
181 goto ret;
182 } else
183 tscadc->irq = err;
01636eb9 184
924ff918
JH
185 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
186 tscadc->tscadc_base = devm_ioremap_resource(&pdev->dev, res);
187 if (IS_ERR(tscadc->tscadc_base))
188 return PTR_ERR(tscadc->tscadc_base);
01636eb9 189
0d3a7cce 190 tscadc->regmap = devm_regmap_init_mmio(&pdev->dev,
01636eb9 191 tscadc->tscadc_base, &tscadc_regmap_config);
0d3a7cce 192 if (IS_ERR(tscadc->regmap)) {
01636eb9 193 dev_err(&pdev->dev, "regmap init failed\n");
0d3a7cce 194 err = PTR_ERR(tscadc->regmap);
3c39c9c6 195 goto ret;
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196 }
197
abeccee4 198 spin_lock_init(&tscadc->reg_lock);
7ca6740c
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199 init_waitqueue_head(&tscadc->reg_se_wait);
200
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201 pm_runtime_enable(&pdev->dev);
202 pm_runtime_get_sync(&pdev->dev);
203
204 /*
205 * The TSC_ADC_Subsystem has 2 clock domains
206 * OCP_CLK and ADC_CLK.
207 * The ADC clock is expected to run at target of 3MHz,
208 * and expected to capture 12-bit data at a rate of 200 KSPS.
209 * The TSC_ADC_SS controller design assumes the OCP clock is
210 * at least 6x faster than the ADC clock.
211 */
212 clk = clk_get(&pdev->dev, "adc_tsc_fck");
213 if (IS_ERR(clk)) {
214 dev_err(&pdev->dev, "failed to get TSC fck\n");
215 err = PTR_ERR(clk);
216 goto err_disable_clk;
217 }
218 clock_rate = clk_get_rate(clk);
219 clk_put(clk);
e90f8754 220 tscadc->clk_div = clock_rate / ADC_CLK;
efe3126a 221
01636eb9 222 /* TSCADC_CLKDIV needs to be configured to the value minus 1 */
e90f8754 223 tscadc->clk_div--;
0d3a7cce 224 regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div);
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225
226 /* Set the control register bits */
f0933a60 227 ctrl = CNTRLREG_STEPCONFIGWRT | CNTRLREG_STEPID;
0d3a7cce 228 regmap_write(tscadc->regmap, REG_CTRL, ctrl);
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229
230 /* Set register bits for Idle Config Mode */
f0933a60
JL
231 if (tsc_wires > 0) {
232 tscadc->tsc_wires = tsc_wires;
233 if (tsc_wires == 5)
234 ctrl |= CNTRLREG_5WIRE | CNTRLREG_TSCENB;
235 else
236 ctrl |= CNTRLREG_4WIRE | CNTRLREG_TSCENB;
b5f8b763 237 tscadc_idle_config(tscadc);
f0933a60 238 }
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239
240 /* Enable the TSC module enable bit */
01636eb9 241 ctrl |= CNTRLREG_TSCSSENB;
0d3a7cce 242 regmap_write(tscadc->regmap, REG_CTRL, ctrl);
01636eb9 243
24d5c82f
PA
244 tscadc->used_cells = 0;
245 tscadc->tsc_cell = -1;
246 tscadc->adc_cell = -1;
247
2b99bafa 248 /* TSC Cell */
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PA
249 if (tsc_wires > 0) {
250 tscadc->tsc_cell = tscadc->used_cells;
251 cell = &tscadc->cells[tscadc->used_cells++];
5f184e63 252 cell->name = "TI-am335x-tsc";
24d5c82f
PA
253 cell->of_compatible = "ti,am3359-tsc";
254 cell->platform_data = &tscadc;
255 cell->pdata_size = sizeof(tscadc);
256 }
2b99bafa 257
5e53a69b 258 /* ADC Cell */
24d5c82f
PA
259 if (adc_channels > 0) {
260 tscadc->adc_cell = tscadc->used_cells;
261 cell = &tscadc->cells[tscadc->used_cells++];
9f99928f 262 cell->name = "TI-am335x-adc";
24d5c82f
PA
263 cell->of_compatible = "ti,am3359-adc";
264 cell->platform_data = &tscadc;
265 cell->pdata_size = sizeof(tscadc);
266 }
5e53a69b 267
01636eb9 268 err = mfd_add_devices(&pdev->dev, pdev->id, tscadc->cells,
24d5c82f 269 tscadc->used_cells, NULL, 0, NULL);
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270 if (err < 0)
271 goto err_disable_clk;
272
273 device_init_wakeup(&pdev->dev, true);
274 platform_set_drvdata(pdev, tscadc);
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275 return 0;
276
277err_disable_clk:
278 pm_runtime_put_sync(&pdev->dev);
279 pm_runtime_disable(&pdev->dev);
3c39c9c6 280ret:
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281 return err;
282}
283
612b95cd 284static int ti_tscadc_remove(struct platform_device *pdev)
01636eb9
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285{
286 struct ti_tscadc_dev *tscadc = platform_get_drvdata(pdev);
287
0d3a7cce 288 regmap_write(tscadc->regmap, REG_SE, 0x00);
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289
290 pm_runtime_put_sync(&pdev->dev);
291 pm_runtime_disable(&pdev->dev);
292
293 mfd_remove_devices(tscadc->dev);
294
295 return 0;
296}
297
dae936a0 298static int __maybe_unused tscadc_suspend(struct device *dev)
01636eb9 299{
a318b7d0 300 struct ti_tscadc_dev *tscadc = dev_get_drvdata(dev);
01636eb9 301
0d3a7cce 302 regmap_write(tscadc->regmap, REG_SE, 0x00);
01636eb9
PR
303 pm_runtime_put_sync(dev);
304
305 return 0;
306}
307
dae936a0 308static int __maybe_unused tscadc_resume(struct device *dev)
01636eb9 309{
a318b7d0 310 struct ti_tscadc_dev *tscadc = dev_get_drvdata(dev);
f0933a60 311 u32 ctrl;
01636eb9
PR
312
313 pm_runtime_get_sync(dev);
314
315 /* context restore */
b5f8b763 316 ctrl = CNTRLREG_STEPCONFIGWRT | CNTRLREG_STEPID;
0d3a7cce 317 regmap_write(tscadc->regmap, REG_CTRL, ctrl);
b5f8b763 318
a318b7d0
AD
319 if (tscadc->tsc_cell != -1) {
320 if (tscadc->tsc_wires == 5)
f0933a60
JL
321 ctrl |= CNTRLREG_5WIRE | CNTRLREG_TSCENB;
322 else
323 ctrl |= CNTRLREG_4WIRE | CNTRLREG_TSCENB;
a318b7d0 324 tscadc_idle_config(tscadc);
f0933a60
JL
325 }
326 ctrl |= CNTRLREG_TSCSSENB;
0d3a7cce 327 regmap_write(tscadc->regmap, REG_CTRL, ctrl);
01636eb9 328
0d3a7cce 329 regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div);
e90f8754 330
01636eb9
PR
331 return 0;
332}
333
dae936a0 334static SIMPLE_DEV_PM_OPS(tscadc_pm_ops, tscadc_suspend, tscadc_resume);
01636eb9 335
a6543a1c
PR
336static const struct of_device_id ti_tscadc_dt_ids[] = {
337 { .compatible = "ti,am3359-tscadc", },
338 { }
339};
340MODULE_DEVICE_TABLE(of, ti_tscadc_dt_ids);
341
01636eb9
PR
342static struct platform_driver ti_tscadc_driver = {
343 .driver = {
a6543a1c 344 .name = "ti_am3359-tscadc",
dae936a0 345 .pm = &tscadc_pm_ops,
131221bc 346 .of_match_table = ti_tscadc_dt_ids,
01636eb9
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347 },
348 .probe = ti_tscadc_probe,
612b95cd 349 .remove = ti_tscadc_remove,
01636eb9
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350
351};
352
353module_platform_driver(ti_tscadc_driver);
354
355MODULE_DESCRIPTION("TI touchscreen / ADC MFD controller driver");
356MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
357MODULE_LICENSE("GPL");