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/init.h>
18 #include <linux/slab.h>
19 #include <linux/err.h>
21 #include <linux/clk.h>
22 #include <linux/regmap.h>
23 #include <linux/mfd/core.h>
24 #include <linux/pm_runtime.h>
26 #include <linux/of_device.h>
28 #include <linux/mfd/ti_am335x_tscadc.h>
30 static unsigned int tscadc_readl(struct ti_tscadc_dev
*tsadc
, unsigned int reg
)
34 regmap_read(tsadc
->regmap_tscadc
, reg
, &val
);
38 static void tscadc_writel(struct ti_tscadc_dev
*tsadc
, unsigned int reg
,
41 regmap_write(tsadc
->regmap_tscadc
, reg
, val
);
44 static const struct regmap_config tscadc_regmap_config
= {
51 void am335x_tsc_se_update(struct ti_tscadc_dev
*tsadc
)
53 tscadc_writel(tsadc
, REG_SE
, tsadc
->reg_se_cache
);
55 EXPORT_SYMBOL_GPL(am335x_tsc_se_update
);
57 void am335x_tsc_se_set(struct ti_tscadc_dev
*tsadc
, u32 val
)
61 spin_lock_irqsave(&tsadc
->reg_lock
, flags
);
62 tsadc
->reg_se_cache
= tscadc_readl(tsadc
, REG_SE
);
63 tsadc
->reg_se_cache
|= val
;
64 am335x_tsc_se_update(tsadc
);
65 spin_unlock_irqrestore(&tsadc
->reg_lock
, flags
);
67 EXPORT_SYMBOL_GPL(am335x_tsc_se_set
);
69 void am335x_tsc_se_clr(struct ti_tscadc_dev
*tsadc
, u32 val
)
73 spin_lock_irqsave(&tsadc
->reg_lock
, flags
);
74 tsadc
->reg_se_cache
= tscadc_readl(tsadc
, REG_SE
);
75 tsadc
->reg_se_cache
&= ~val
;
76 am335x_tsc_se_update(tsadc
);
77 spin_unlock_irqrestore(&tsadc
->reg_lock
, flags
);
79 EXPORT_SYMBOL_GPL(am335x_tsc_se_clr
);
81 static void tscadc_idle_config(struct ti_tscadc_dev
*config
)
83 unsigned int idleconfig
;
85 idleconfig
= STEPCONFIG_YNN
| STEPCONFIG_INM_ADCREFM
|
86 STEPCONFIG_INP_ADCREFM
| STEPCONFIG_YPN
;
88 tscadc_writel(config
, REG_IDLECONFIG
, idleconfig
);
91 static int ti_tscadc_probe(struct platform_device
*pdev
)
93 struct ti_tscadc_dev
*tscadc
;
96 struct device_node
*node
= pdev
->dev
.of_node
;
97 struct mfd_cell
*cell
;
98 struct property
*prop
;
103 int tsc_wires
= 0, adc_channels
= 0, total_channels
;
106 if (!pdev
->dev
.of_node
) {
107 dev_err(&pdev
->dev
, "Could not find valid DT data.\n");
111 node
= of_get_child_by_name(pdev
->dev
.of_node
, "tsc");
112 of_property_read_u32(node
, "ti,wires", &tsc_wires
);
113 of_property_read_u32(node
, "ti,coordiante-readouts", &readouts
);
115 node
= of_get_child_by_name(pdev
->dev
.of_node
, "adc");
116 of_property_for_each_u32(node
, "ti,adc-channels", prop
, cur
, val
) {
119 dev_err(&pdev
->dev
, " PIN numbers are 0..7 (not %d)\n",
124 total_channels
= tsc_wires
+ adc_channels
;
125 if (total_channels
> 8) {
126 dev_err(&pdev
->dev
, "Number of i/p channels more than 8\n");
129 if (total_channels
== 0) {
130 dev_err(&pdev
->dev
, "Need atleast one channel.\n");
134 if (readouts
* 2 + 2 + adc_channels
> 16) {
135 dev_err(&pdev
->dev
, "Too many step configurations requested\n");
139 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
141 dev_err(&pdev
->dev
, "no memory resource defined.\n");
145 /* Allocate memory for device */
146 tscadc
= devm_kzalloc(&pdev
->dev
,
147 sizeof(struct ti_tscadc_dev
), GFP_KERNEL
);
149 dev_err(&pdev
->dev
, "failed to allocate memory.\n");
152 tscadc
->dev
= &pdev
->dev
;
154 err
= platform_get_irq(pdev
, 0);
156 dev_err(&pdev
->dev
, "no irq ID is specified.\n");
161 res
= devm_request_mem_region(&pdev
->dev
,
162 res
->start
, resource_size(res
), pdev
->name
);
164 dev_err(&pdev
->dev
, "failed to reserve registers.\n");
168 tscadc
->tscadc_base
= devm_ioremap(&pdev
->dev
,
169 res
->start
, resource_size(res
));
170 if (!tscadc
->tscadc_base
) {
171 dev_err(&pdev
->dev
, "failed to map registers.\n");
175 tscadc
->regmap_tscadc
= devm_regmap_init_mmio(&pdev
->dev
,
176 tscadc
->tscadc_base
, &tscadc_regmap_config
);
177 if (IS_ERR(tscadc
->regmap_tscadc
)) {
178 dev_err(&pdev
->dev
, "regmap init failed\n");
179 err
= PTR_ERR(tscadc
->regmap_tscadc
);
183 spin_lock_init(&tscadc
->reg_lock
);
184 pm_runtime_enable(&pdev
->dev
);
185 pm_runtime_get_sync(&pdev
->dev
);
188 * The TSC_ADC_Subsystem has 2 clock domains
189 * OCP_CLK and ADC_CLK.
190 * The ADC clock is expected to run at target of 3MHz,
191 * and expected to capture 12-bit data at a rate of 200 KSPS.
192 * The TSC_ADC_SS controller design assumes the OCP clock is
193 * at least 6x faster than the ADC clock.
195 clk
= clk_get(&pdev
->dev
, "adc_tsc_fck");
197 dev_err(&pdev
->dev
, "failed to get TSC fck\n");
199 goto err_disable_clk
;
201 clock_rate
= clk_get_rate(clk
);
203 tscadc
->clk_div
= clock_rate
/ ADC_CLK
;
205 /* TSCADC_CLKDIV needs to be configured to the value minus 1 */
207 tscadc_writel(tscadc
, REG_CLKDIV
, tscadc
->clk_div
);
209 /* Set the control register bits */
210 ctrl
= CNTRLREG_STEPCONFIGWRT
|
213 ctrl
|= CNTRLREG_4WIRE
| CNTRLREG_TSCENB
;
214 tscadc_writel(tscadc
, REG_CTRL
, ctrl
);
216 /* Set register bits for Idle Config Mode */
218 tscadc_idle_config(tscadc
);
220 /* Enable the TSC module enable bit */
221 ctrl
= tscadc_readl(tscadc
, REG_CTRL
);
222 ctrl
|= CNTRLREG_TSCSSENB
;
223 tscadc_writel(tscadc
, REG_CTRL
, ctrl
);
225 tscadc
->used_cells
= 0;
226 tscadc
->tsc_cell
= -1;
227 tscadc
->adc_cell
= -1;
231 tscadc
->tsc_cell
= tscadc
->used_cells
;
232 cell
= &tscadc
->cells
[tscadc
->used_cells
++];
233 cell
->name
= "TI-am335x-tsc";
234 cell
->of_compatible
= "ti,am3359-tsc";
235 cell
->platform_data
= &tscadc
;
236 cell
->pdata_size
= sizeof(tscadc
);
240 if (adc_channels
> 0) {
241 tscadc
->adc_cell
= tscadc
->used_cells
;
242 cell
= &tscadc
->cells
[tscadc
->used_cells
++];
243 cell
->name
= "TI-am335x-adc";
244 cell
->of_compatible
= "ti,am3359-adc";
245 cell
->platform_data
= &tscadc
;
246 cell
->pdata_size
= sizeof(tscadc
);
249 err
= mfd_add_devices(&pdev
->dev
, pdev
->id
, tscadc
->cells
,
250 tscadc
->used_cells
, NULL
, 0, NULL
);
252 goto err_disable_clk
;
254 device_init_wakeup(&pdev
->dev
, true);
255 platform_set_drvdata(pdev
, tscadc
);
259 pm_runtime_put_sync(&pdev
->dev
);
260 pm_runtime_disable(&pdev
->dev
);
265 static int ti_tscadc_remove(struct platform_device
*pdev
)
267 struct ti_tscadc_dev
*tscadc
= platform_get_drvdata(pdev
);
269 tscadc_writel(tscadc
, REG_SE
, 0x00);
271 pm_runtime_put_sync(&pdev
->dev
);
272 pm_runtime_disable(&pdev
->dev
);
274 mfd_remove_devices(tscadc
->dev
);
280 static int tscadc_suspend(struct device
*dev
)
282 struct ti_tscadc_dev
*tscadc_dev
= dev_get_drvdata(dev
);
284 tscadc_writel(tscadc_dev
, REG_SE
, 0x00);
285 pm_runtime_put_sync(dev
);
290 static int tscadc_resume(struct device
*dev
)
292 struct ti_tscadc_dev
*tscadc_dev
= dev_get_drvdata(dev
);
293 unsigned int restore
, ctrl
;
295 pm_runtime_get_sync(dev
);
297 /* context restore */
298 ctrl
= CNTRLREG_STEPCONFIGWRT
| CNTRLREG_STEPID
;
299 if (tscadc_dev
->tsc_cell
!= -1)
300 ctrl
|= CNTRLREG_TSCENB
| CNTRLREG_4WIRE
;
301 tscadc_writel(tscadc_dev
, REG_CTRL
, ctrl
);
303 if (tscadc_dev
->tsc_cell
!= -1)
304 tscadc_idle_config(tscadc_dev
);
305 am335x_tsc_se_update(tscadc_dev
);
306 restore
= tscadc_readl(tscadc_dev
, REG_CTRL
);
307 tscadc_writel(tscadc_dev
, REG_CTRL
,
308 (restore
| CNTRLREG_TSCSSENB
));
310 tscadc_writel(tscadc_dev
, REG_CLKDIV
, tscadc_dev
->clk_div
);
315 static const struct dev_pm_ops tscadc_pm_ops
= {
316 .suspend
= tscadc_suspend
,
317 .resume
= tscadc_resume
,
319 #define TSCADC_PM_OPS (&tscadc_pm_ops)
321 #define TSCADC_PM_OPS NULL
324 static const struct of_device_id ti_tscadc_dt_ids
[] = {
325 { .compatible
= "ti,am3359-tscadc", },
328 MODULE_DEVICE_TABLE(of
, ti_tscadc_dt_ids
);
330 static struct platform_driver ti_tscadc_driver
= {
332 .name
= "ti_am3359-tscadc",
333 .owner
= THIS_MODULE
,
335 .of_match_table
= ti_tscadc_dt_ids
,
337 .probe
= ti_tscadc_probe
,
338 .remove
= ti_tscadc_remove
,
342 module_platform_driver(ti_tscadc_driver
);
344 MODULE_DESCRIPTION("TI touchscreen / ADC MFD controller driver");
345 MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
346 MODULE_LICENSE("GPL");