2 * TI Touch Screen / ADC MFD driver
4 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
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.
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.
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/err.h>
20 #include <linux/clk.h>
21 #include <linux/regmap.h>
22 #include <linux/mfd/core.h>
23 #include <linux/pm_runtime.h>
25 #include <linux/of_device.h>
26 #include <linux/sched.h>
28 #include <linux/mfd/ti_am335x_tscadc.h>
30 static const struct regmap_config tscadc_regmap_config
= {
37 void am335x_tsc_se_set_cache(struct ti_tscadc_dev
*tscadc
, u32 val
)
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
)
46 regmap_write(tscadc
->regmap
, REG_SE
, tscadc
->reg_se_cache
);
48 spin_unlock_irqrestore(&tscadc
->reg_lock
, flags
);
50 EXPORT_SYMBOL_GPL(am335x_tsc_se_set_cache
);
52 static void am335x_tscadc_need_adc(struct ti_tscadc_dev
*tscadc
)
57 regmap_read(tscadc
->regmap
, REG_ADCFSM
, ®
);
58 if (reg
& SEQ_STATUS
) {
59 tscadc
->adc_waiting
= true;
60 prepare_to_wait(&tscadc
->reg_se_wait
, &wait
,
61 TASK_UNINTERRUPTIBLE
);
62 spin_unlock_irq(&tscadc
->reg_lock
);
66 spin_lock_irq(&tscadc
->reg_lock
);
67 finish_wait(&tscadc
->reg_se_wait
, &wait
);
70 * Sequencer should either be idle or
71 * busy applying the charge step.
73 regmap_read(tscadc
->regmap
, REG_ADCFSM
, ®
);
74 WARN_ON((reg
& SEQ_STATUS
) && !(reg
& CHARGE_STEP
));
75 tscadc
->adc_waiting
= false;
77 tscadc
->adc_in_use
= true;
80 void am335x_tsc_se_set_once(struct ti_tscadc_dev
*tscadc
, u32 val
)
82 spin_lock_irq(&tscadc
->reg_lock
);
83 am335x_tscadc_need_adc(tscadc
);
85 regmap_write(tscadc
->regmap
, REG_SE
, val
);
86 spin_unlock_irq(&tscadc
->reg_lock
);
88 EXPORT_SYMBOL_GPL(am335x_tsc_se_set_once
);
90 void am335x_tsc_se_adc_done(struct ti_tscadc_dev
*tscadc
)
94 spin_lock_irqsave(&tscadc
->reg_lock
, flags
);
95 tscadc
->adc_in_use
= false;
96 regmap_write(tscadc
->regmap
, REG_SE
, tscadc
->reg_se_cache
);
97 spin_unlock_irqrestore(&tscadc
->reg_lock
, flags
);
99 EXPORT_SYMBOL_GPL(am335x_tsc_se_adc_done
);
101 void am335x_tsc_se_clr(struct ti_tscadc_dev
*tscadc
, u32 val
)
105 spin_lock_irqsave(&tscadc
->reg_lock
, flags
);
106 tscadc
->reg_se_cache
&= ~val
;
107 regmap_write(tscadc
->regmap
, REG_SE
, tscadc
->reg_se_cache
);
108 spin_unlock_irqrestore(&tscadc
->reg_lock
, flags
);
110 EXPORT_SYMBOL_GPL(am335x_tsc_se_clr
);
112 static void tscadc_idle_config(struct ti_tscadc_dev
*tscadc
)
114 unsigned int idleconfig
;
116 idleconfig
= STEPCONFIG_YNN
| STEPCONFIG_INM_ADCREFM
|
117 STEPCONFIG_INP_ADCREFM
| STEPCONFIG_YPN
;
119 regmap_write(tscadc
->regmap
, REG_IDLECONFIG
, idleconfig
);
122 static int ti_tscadc_probe(struct platform_device
*pdev
)
124 struct ti_tscadc_dev
*tscadc
;
125 struct resource
*res
;
127 struct device_node
*node
;
128 struct mfd_cell
*cell
;
129 struct property
*prop
;
134 int tsc_wires
= 0, adc_channels
= 0, total_channels
;
137 if (!pdev
->dev
.of_node
) {
138 dev_err(&pdev
->dev
, "Could not find valid DT data.\n");
142 node
= of_get_child_by_name(pdev
->dev
.of_node
, "tsc");
143 of_property_read_u32(node
, "ti,wires", &tsc_wires
);
144 of_property_read_u32(node
, "ti,coordiante-readouts", &readouts
);
146 node
= of_get_child_by_name(pdev
->dev
.of_node
, "adc");
147 of_property_for_each_u32(node
, "ti,adc-channels", prop
, cur
, val
) {
150 dev_err(&pdev
->dev
, " PIN numbers are 0..7 (not %d)\n",
155 total_channels
= tsc_wires
+ adc_channels
;
156 if (total_channels
> 8) {
157 dev_err(&pdev
->dev
, "Number of i/p channels more than 8\n");
160 if (total_channels
== 0) {
161 dev_err(&pdev
->dev
, "Need atleast one channel.\n");
165 if (readouts
* 2 + 2 + adc_channels
> 16) {
166 dev_err(&pdev
->dev
, "Too many step configurations requested\n");
170 /* Allocate memory for device */
171 tscadc
= devm_kzalloc(&pdev
->dev
, sizeof(*tscadc
), GFP_KERNEL
);
175 tscadc
->dev
= &pdev
->dev
;
177 err
= platform_get_irq(pdev
, 0);
179 dev_err(&pdev
->dev
, "no irq ID is specified.\n");
184 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
185 tscadc
->tscadc_phys_base
= res
->start
;
186 tscadc
->tscadc_base
= devm_ioremap_resource(&pdev
->dev
, res
);
187 if (IS_ERR(tscadc
->tscadc_base
))
188 return PTR_ERR(tscadc
->tscadc_base
);
190 tscadc
->regmap
= devm_regmap_init_mmio(&pdev
->dev
,
191 tscadc
->tscadc_base
, &tscadc_regmap_config
);
192 if (IS_ERR(tscadc
->regmap
)) {
193 dev_err(&pdev
->dev
, "regmap init failed\n");
194 err
= PTR_ERR(tscadc
->regmap
);
198 spin_lock_init(&tscadc
->reg_lock
);
199 init_waitqueue_head(&tscadc
->reg_se_wait
);
201 pm_runtime_enable(&pdev
->dev
);
202 pm_runtime_get_sync(&pdev
->dev
);
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.
212 clk
= devm_clk_get(&pdev
->dev
, "adc_tsc_fck");
214 dev_err(&pdev
->dev
, "failed to get TSC fck\n");
216 goto err_disable_clk
;
218 clock_rate
= clk_get_rate(clk
);
219 tscadc
->clk_div
= clock_rate
/ ADC_CLK
;
221 /* TSCADC_CLKDIV needs to be configured to the value minus 1 */
223 regmap_write(tscadc
->regmap
, REG_CLKDIV
, tscadc
->clk_div
);
225 /* Set the control register bits */
226 ctrl
= CNTRLREG_STEPCONFIGWRT
| CNTRLREG_STEPID
;
227 regmap_write(tscadc
->regmap
, REG_CTRL
, ctrl
);
229 /* Set register bits for Idle Config Mode */
231 tscadc
->tsc_wires
= tsc_wires
;
233 ctrl
|= CNTRLREG_5WIRE
| CNTRLREG_TSCENB
;
235 ctrl
|= CNTRLREG_4WIRE
| CNTRLREG_TSCENB
;
236 tscadc_idle_config(tscadc
);
239 /* Enable the TSC module enable bit */
240 ctrl
|= CNTRLREG_TSCSSENB
;
241 regmap_write(tscadc
->regmap
, REG_CTRL
, ctrl
);
243 tscadc
->used_cells
= 0;
244 tscadc
->tsc_cell
= -1;
245 tscadc
->adc_cell
= -1;
249 tscadc
->tsc_cell
= tscadc
->used_cells
;
250 cell
= &tscadc
->cells
[tscadc
->used_cells
++];
251 cell
->name
= "TI-am335x-tsc";
252 cell
->of_compatible
= "ti,am3359-tsc";
253 cell
->platform_data
= &tscadc
;
254 cell
->pdata_size
= sizeof(tscadc
);
258 if (adc_channels
> 0) {
259 tscadc
->adc_cell
= tscadc
->used_cells
;
260 cell
= &tscadc
->cells
[tscadc
->used_cells
++];
261 cell
->name
= "TI-am335x-adc";
262 cell
->of_compatible
= "ti,am3359-adc";
263 cell
->platform_data
= &tscadc
;
264 cell
->pdata_size
= sizeof(tscadc
);
267 err
= mfd_add_devices(&pdev
->dev
, pdev
->id
, tscadc
->cells
,
268 tscadc
->used_cells
, NULL
, 0, NULL
);
270 goto err_disable_clk
;
272 device_init_wakeup(&pdev
->dev
, true);
273 platform_set_drvdata(pdev
, tscadc
);
277 pm_runtime_put_sync(&pdev
->dev
);
278 pm_runtime_disable(&pdev
->dev
);
283 static int ti_tscadc_remove(struct platform_device
*pdev
)
285 struct ti_tscadc_dev
*tscadc
= platform_get_drvdata(pdev
);
287 regmap_write(tscadc
->regmap
, REG_SE
, 0x00);
289 pm_runtime_put_sync(&pdev
->dev
);
290 pm_runtime_disable(&pdev
->dev
);
292 mfd_remove_devices(tscadc
->dev
);
297 static int __maybe_unused
tscadc_suspend(struct device
*dev
)
299 struct ti_tscadc_dev
*tscadc
= dev_get_drvdata(dev
);
301 regmap_write(tscadc
->regmap
, REG_SE
, 0x00);
302 pm_runtime_put_sync(dev
);
307 static int __maybe_unused
tscadc_resume(struct device
*dev
)
309 struct ti_tscadc_dev
*tscadc
= dev_get_drvdata(dev
);
312 pm_runtime_get_sync(dev
);
314 /* context restore */
315 ctrl
= CNTRLREG_STEPCONFIGWRT
| CNTRLREG_STEPID
;
316 regmap_write(tscadc
->regmap
, REG_CTRL
, ctrl
);
318 if (tscadc
->tsc_cell
!= -1) {
319 if (tscadc
->tsc_wires
== 5)
320 ctrl
|= CNTRLREG_5WIRE
| CNTRLREG_TSCENB
;
322 ctrl
|= CNTRLREG_4WIRE
| CNTRLREG_TSCENB
;
323 tscadc_idle_config(tscadc
);
325 ctrl
|= CNTRLREG_TSCSSENB
;
326 regmap_write(tscadc
->regmap
, REG_CTRL
, ctrl
);
328 regmap_write(tscadc
->regmap
, REG_CLKDIV
, tscadc
->clk_div
);
333 static SIMPLE_DEV_PM_OPS(tscadc_pm_ops
, tscadc_suspend
, tscadc_resume
);
335 static const struct of_device_id ti_tscadc_dt_ids
[] = {
336 { .compatible
= "ti,am3359-tscadc", },
339 MODULE_DEVICE_TABLE(of
, ti_tscadc_dt_ids
);
341 static struct platform_driver ti_tscadc_driver
= {
343 .name
= "ti_am3359-tscadc",
344 .pm
= &tscadc_pm_ops
,
345 .of_match_table
= ti_tscadc_dt_ids
,
347 .probe
= ti_tscadc_probe
,
348 .remove
= ti_tscadc_remove
,
352 module_platform_driver(ti_tscadc_driver
);
354 MODULE_DESCRIPTION("TI touchscreen / ADC MFD controller driver");
355 MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
356 MODULE_LICENSE("GPL");