linux/drivers/mfd/ti_am335x_tscadc.c
Rob Herring dc0c386e09 mfd: Explicitly include correct DT includes
The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230714174731.4059811-1-robh@kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>
2023-08-18 21:48:03 +01:00

393 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* TI Touch Screen / ADC MFD driver
*
* Copyright (C) 2012 Texas Instruments Incorporated - https://www.ti.com/
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/regmap.h>
#include <linux/mfd/core.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/mfd/ti_am335x_tscadc.h>
static const struct regmap_config tscadc_regmap_config = {
.name = "ti_tscadc",
.reg_bits = 32,
.reg_stride = 4,
.val_bits = 32,
};
void am335x_tsc_se_set_cache(struct ti_tscadc_dev *tscadc, u32 val)
{
unsigned long flags;
spin_lock_irqsave(&tscadc->reg_lock, flags);
tscadc->reg_se_cache |= val;
if (tscadc->adc_waiting)
wake_up(&tscadc->reg_se_wait);
else if (!tscadc->adc_in_use)
regmap_write(tscadc->regmap, REG_SE, tscadc->reg_se_cache);
spin_unlock_irqrestore(&tscadc->reg_lock, flags);
}
EXPORT_SYMBOL_GPL(am335x_tsc_se_set_cache);
static void am335x_tscadc_need_adc(struct ti_tscadc_dev *tscadc)
{
DEFINE_WAIT(wait);
u32 reg;
regmap_read(tscadc->regmap, REG_ADCFSM, &reg);
if (reg & SEQ_STATUS) {
tscadc->adc_waiting = true;
prepare_to_wait(&tscadc->reg_se_wait, &wait,
TASK_UNINTERRUPTIBLE);
spin_unlock_irq(&tscadc->reg_lock);
schedule();
spin_lock_irq(&tscadc->reg_lock);
finish_wait(&tscadc->reg_se_wait, &wait);
/*
* Sequencer should either be idle or
* busy applying the charge step.
*/
regmap_read(tscadc->regmap, REG_ADCFSM, &reg);
WARN_ON((reg & SEQ_STATUS) && !(reg & CHARGE_STEP));
tscadc->adc_waiting = false;
}
tscadc->adc_in_use = true;
}
void am335x_tsc_se_set_once(struct ti_tscadc_dev *tscadc, u32 val)
{
spin_lock_irq(&tscadc->reg_lock);
am335x_tscadc_need_adc(tscadc);
regmap_write(tscadc->regmap, REG_SE, val);
spin_unlock_irq(&tscadc->reg_lock);
}
EXPORT_SYMBOL_GPL(am335x_tsc_se_set_once);
void am335x_tsc_se_adc_done(struct ti_tscadc_dev *tscadc)
{
unsigned long flags;
spin_lock_irqsave(&tscadc->reg_lock, flags);
tscadc->adc_in_use = false;
regmap_write(tscadc->regmap, REG_SE, tscadc->reg_se_cache);
spin_unlock_irqrestore(&tscadc->reg_lock, flags);
}
EXPORT_SYMBOL_GPL(am335x_tsc_se_adc_done);
void am335x_tsc_se_clr(struct ti_tscadc_dev *tscadc, u32 val)
{
unsigned long flags;
spin_lock_irqsave(&tscadc->reg_lock, flags);
tscadc->reg_se_cache &= ~val;
regmap_write(tscadc->regmap, REG_SE, tscadc->reg_se_cache);
spin_unlock_irqrestore(&tscadc->reg_lock, flags);
}
EXPORT_SYMBOL_GPL(am335x_tsc_se_clr);
static void tscadc_idle_config(struct ti_tscadc_dev *tscadc)
{
unsigned int idleconfig;
idleconfig = STEPCONFIG_INM_ADCREFM | STEPCONFIG_INP_ADCREFM;
if (ti_adc_with_touchscreen(tscadc))
idleconfig |= STEPCONFIG_YNN | STEPCONFIG_YPN;
regmap_write(tscadc->regmap, REG_IDLECONFIG, idleconfig);
}
static int ti_tscadc_probe(struct platform_device *pdev)
{
struct ti_tscadc_dev *tscadc;
struct resource *res;
struct clk *clk;
struct device_node *node;
struct mfd_cell *cell;
struct property *prop;
const __be32 *cur;
bool use_tsc = false, use_mag = false;
u32 val;
int err;
int tscmag_wires = 0, adc_channels = 0, cell_idx = 0, total_channels;
int readouts = 0, mag_tracks = 0;
/* Allocate memory for device */
tscadc = devm_kzalloc(&pdev->dev, sizeof(*tscadc), GFP_KERNEL);
if (!tscadc)
return -ENOMEM;
tscadc->dev = &pdev->dev;
if (!pdev->dev.of_node) {
dev_err(&pdev->dev, "Could not find valid DT data.\n");
return -EINVAL;
}
tscadc->data = of_device_get_match_data(&pdev->dev);
if (ti_adc_with_touchscreen(tscadc)) {
node = of_get_child_by_name(pdev->dev.of_node, "tsc");
of_property_read_u32(node, "ti,wires", &tscmag_wires);
err = of_property_read_u32(node, "ti,coordinate-readouts",
&readouts);
if (err < 0)
of_property_read_u32(node, "ti,coordiante-readouts",
&readouts);
of_node_put(node);
if (tscmag_wires)
use_tsc = true;
} else {
/*
* When adding support for the magnetic stripe reader, here is
* the place to look for the number of tracks used from device
* tree. Let's default to 0 for now.
*/
mag_tracks = 0;
tscmag_wires = mag_tracks * 2;
if (tscmag_wires)
use_mag = true;
}
node = of_get_child_by_name(pdev->dev.of_node, "adc");
of_property_for_each_u32(node, "ti,adc-channels", prop, cur, val) {
adc_channels++;
if (val > 7) {
dev_err(&pdev->dev, " PIN numbers are 0..7 (not %d)\n",
val);
of_node_put(node);
return -EINVAL;
}
}
of_node_put(node);
total_channels = tscmag_wires + adc_channels;
if (total_channels > 8) {
dev_err(&pdev->dev, "Number of i/p channels more than 8\n");
return -EINVAL;
}
if (total_channels == 0) {
dev_err(&pdev->dev, "Need at least one channel.\n");
return -EINVAL;
}
if (use_tsc && (readouts * 2 + 2 + adc_channels > 16)) {
dev_err(&pdev->dev, "Too many step configurations requested\n");
return -EINVAL;
}
err = platform_get_irq(pdev, 0);
if (err < 0)
return err;
else
tscadc->irq = err;
tscadc->tscadc_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
if (IS_ERR(tscadc->tscadc_base))
return PTR_ERR(tscadc->tscadc_base);
tscadc->tscadc_phys_base = res->start;
tscadc->regmap = devm_regmap_init_mmio(&pdev->dev,
tscadc->tscadc_base,
&tscadc_regmap_config);
if (IS_ERR(tscadc->regmap)) {
dev_err(&pdev->dev, "regmap init failed\n");
return PTR_ERR(tscadc->regmap);
}
spin_lock_init(&tscadc->reg_lock);
init_waitqueue_head(&tscadc->reg_se_wait);
pm_runtime_enable(&pdev->dev);
pm_runtime_get_sync(&pdev->dev);
/*
* The TSC_ADC_Subsystem has 2 clock domains: OCP_CLK and ADC_CLK.
* ADCs produce a 12-bit sample every 15 ADC_CLK cycles.
* am33xx ADCs expect to capture 200ksps.
* am47xx ADCs expect to capture 867ksps.
* We need ADC clocks respectively running at 3MHz and 13MHz.
* These frequencies are valid since TSC_ADC_SS controller design
* assumes the OCP clock is at least 6x faster than the ADC clock.
*/
clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(clk)) {
dev_err(&pdev->dev, "failed to get fck\n");
err = PTR_ERR(clk);
goto err_disable_clk;
}
tscadc->clk_div = (clk_get_rate(clk) / tscadc->data->target_clk_rate) - 1;
regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div);
/*
* Set the control register bits. tscadc->ctrl stores the configuration
* of the CTRL register but not the subsystem enable bit which must be
* added manually when timely.
*/
tscadc->ctrl = CNTRLREG_STEPID;
if (ti_adc_with_touchscreen(tscadc)) {
tscadc->ctrl |= CNTRLREG_TSC_STEPCONFIGWRT;
if (use_tsc) {
tscadc->ctrl |= CNTRLREG_TSC_ENB;
if (tscmag_wires == 5)
tscadc->ctrl |= CNTRLREG_TSC_5WIRE;
else
tscadc->ctrl |= CNTRLREG_TSC_4WIRE;
}
} else {
tscadc->ctrl |= CNTRLREG_MAG_PREAMP_PWRDOWN |
CNTRLREG_MAG_PREAMP_BYPASS;
}
regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl);
tscadc_idle_config(tscadc);
/* Enable the TSC module enable bit */
regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl | CNTRLREG_SSENB);
/* TSC or MAG Cell */
if (use_tsc || use_mag) {
cell = &tscadc->cells[cell_idx++];
cell->name = tscadc->data->secondary_feature_name;
cell->of_compatible = tscadc->data->secondary_feature_compatible;
cell->platform_data = &tscadc;
cell->pdata_size = sizeof(tscadc);
}
/* ADC Cell */
if (adc_channels > 0) {
cell = &tscadc->cells[cell_idx++];
cell->name = tscadc->data->adc_feature_name;
cell->of_compatible = tscadc->data->adc_feature_compatible;
cell->platform_data = &tscadc;
cell->pdata_size = sizeof(tscadc);
}
err = mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO,
tscadc->cells, cell_idx, NULL, 0, NULL);
if (err < 0)
goto err_disable_clk;
platform_set_drvdata(pdev, tscadc);
return 0;
err_disable_clk:
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
return err;
}
static int ti_tscadc_remove(struct platform_device *pdev)
{
struct ti_tscadc_dev *tscadc = platform_get_drvdata(pdev);
regmap_write(tscadc->regmap, REG_SE, 0x00);
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
mfd_remove_devices(tscadc->dev);
return 0;
}
static int __maybe_unused ti_tscadc_can_wakeup(struct device *dev, void *data)
{
return device_may_wakeup(dev);
}
static int __maybe_unused tscadc_suspend(struct device *dev)
{
struct ti_tscadc_dev *tscadc = dev_get_drvdata(dev);
regmap_write(tscadc->regmap, REG_SE, 0x00);
if (device_for_each_child(dev, NULL, ti_tscadc_can_wakeup)) {
u32 ctrl;
regmap_read(tscadc->regmap, REG_CTRL, &ctrl);
ctrl &= ~(CNTRLREG_POWERDOWN);
ctrl |= CNTRLREG_SSENB;
regmap_write(tscadc->regmap, REG_CTRL, ctrl);
}
pm_runtime_put_sync(dev);
return 0;
}
static int __maybe_unused tscadc_resume(struct device *dev)
{
struct ti_tscadc_dev *tscadc = dev_get_drvdata(dev);
pm_runtime_get_sync(dev);
regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div);
regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl);
tscadc_idle_config(tscadc);
regmap_write(tscadc->regmap, REG_CTRL, tscadc->ctrl | CNTRLREG_SSENB);
return 0;
}
static SIMPLE_DEV_PM_OPS(tscadc_pm_ops, tscadc_suspend, tscadc_resume);
static const struct ti_tscadc_data tscdata = {
.adc_feature_name = "TI-am335x-adc",
.adc_feature_compatible = "ti,am3359-adc",
.secondary_feature_name = "TI-am335x-tsc",
.secondary_feature_compatible = "ti,am3359-tsc",
.target_clk_rate = TSC_ADC_CLK,
};
static const struct ti_tscadc_data magdata = {
.adc_feature_name = "TI-am43xx-adc",
.adc_feature_compatible = "ti,am4372-adc",
.secondary_feature_name = "TI-am43xx-mag",
.secondary_feature_compatible = "ti,am4372-mag",
.target_clk_rate = MAG_ADC_CLK,
};
static const struct of_device_id ti_tscadc_dt_ids[] = {
{ .compatible = "ti,am3359-tscadc", .data = &tscdata },
{ .compatible = "ti,am4372-magadc", .data = &magdata },
{ }
};
MODULE_DEVICE_TABLE(of, ti_tscadc_dt_ids);
static struct platform_driver ti_tscadc_driver = {
.driver = {
.name = "ti_am3359-tscadc",
.pm = &tscadc_pm_ops,
.of_match_table = ti_tscadc_dt_ids,
},
.probe = ti_tscadc_probe,
.remove = ti_tscadc_remove,
};
module_platform_driver(ti_tscadc_driver);
MODULE_DESCRIPTION("TI touchscreen/magnetic stripe reader/ADC MFD controller driver");
MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
MODULE_LICENSE("GPL");