linux/drivers/mfd/mxs-lradc.c
Ksenija Stanojevic ead25133e9 mfd: mxs-lradc: Add support for mxs-lradc
Add core files for low resolution analog-to-digital converter (mxs-lradc)
MFD driver.

Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2017-03-23 12:28:28 +00:00

268 lines
7.2 KiB
C

/*
* Freescale MXS Low Resolution Analog-to-Digital Converter driver
*
* Copyright (c) 2012 DENX Software Engineering, GmbH.
* Copyright (c) 2017 Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
*
* Authors:
* Marek Vasut <marex@denx.de>
* Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/mfd/core.h>
#include <linux/mfd/mxs-lradc.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#define ADC_CELL 0
#define TSC_CELL 1
#define RES_MEM 0
enum mx23_lradc_irqs {
MX23_LRADC_TS_IRQ = 0,
MX23_LRADC_CH0_IRQ,
MX23_LRADC_CH1_IRQ,
MX23_LRADC_CH2_IRQ,
MX23_LRADC_CH3_IRQ,
MX23_LRADC_CH4_IRQ,
MX23_LRADC_CH5_IRQ,
MX23_LRADC_CH6_IRQ,
MX23_LRADC_CH7_IRQ,
};
enum mx28_lradc_irqs {
MX28_LRADC_TS_IRQ = 0,
MX28_LRADC_TRESH0_IRQ,
MX28_LRADC_TRESH1_IRQ,
MX28_LRADC_CH0_IRQ,
MX28_LRADC_CH1_IRQ,
MX28_LRADC_CH2_IRQ,
MX28_LRADC_CH3_IRQ,
MX28_LRADC_CH4_IRQ,
MX28_LRADC_CH5_IRQ,
MX28_LRADC_CH6_IRQ,
MX28_LRADC_CH7_IRQ,
MX28_LRADC_BUTTON0_IRQ,
MX28_LRADC_BUTTON1_IRQ,
};
static struct resource mx23_adc_resources[] = {
DEFINE_RES_MEM(0x0, 0x0),
DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH0_IRQ, "mxs-lradc-channel0"),
DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH1_IRQ, "mxs-lradc-channel1"),
DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH2_IRQ, "mxs-lradc-channel2"),
DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH3_IRQ, "mxs-lradc-channel3"),
DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH4_IRQ, "mxs-lradc-channel4"),
DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH5_IRQ, "mxs-lradc-channel5"),
};
static struct resource mx23_touchscreen_resources[] = {
DEFINE_RES_MEM(0x0, 0x0),
DEFINE_RES_IRQ_NAMED(MX23_LRADC_TS_IRQ, "mxs-lradc-touchscreen"),
DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH6_IRQ, "mxs-lradc-channel6"),
DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH7_IRQ, "mxs-lradc-channel7"),
};
static struct resource mx28_adc_resources[] = {
DEFINE_RES_MEM(0x0, 0x0),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_TRESH0_IRQ, "mxs-lradc-thresh0"),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_TRESH1_IRQ, "mxs-lradc-thresh1"),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH0_IRQ, "mxs-lradc-channel0"),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH1_IRQ, "mxs-lradc-channel1"),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH2_IRQ, "mxs-lradc-channel2"),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH3_IRQ, "mxs-lradc-channel3"),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH4_IRQ, "mxs-lradc-channel4"),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH5_IRQ, "mxs-lradc-channel5"),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_BUTTON0_IRQ, "mxs-lradc-button0"),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_BUTTON1_IRQ, "mxs-lradc-button1"),
};
static struct resource mx28_touchscreen_resources[] = {
DEFINE_RES_MEM(0x0, 0x0),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_TS_IRQ, "mxs-lradc-touchscreen"),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH6_IRQ, "mxs-lradc-channel6"),
DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH7_IRQ, "mxs-lradc-channel7"),
};
static struct mfd_cell mx23_cells[] = {
{
.name = "mxs-lradc-adc",
.resources = mx23_adc_resources,
.num_resources = ARRAY_SIZE(mx23_adc_resources),
},
{
.name = "mxs-lradc-ts",
.resources = mx23_touchscreen_resources,
.num_resources = ARRAY_SIZE(mx23_touchscreen_resources),
},
};
static struct mfd_cell mx28_cells[] = {
{
.name = "mxs-lradc-adc",
.resources = mx28_adc_resources,
.num_resources = ARRAY_SIZE(mx28_adc_resources),
},
{
.name = "mxs-lradc-ts",
.resources = mx28_touchscreen_resources,
.num_resources = ARRAY_SIZE(mx28_touchscreen_resources),
}
};
static const struct of_device_id mxs_lradc_dt_ids[] = {
{ .compatible = "fsl,imx23-lradc", .data = (void *)IMX23_LRADC, },
{ .compatible = "fsl,imx28-lradc", .data = (void *)IMX28_LRADC, },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids);
static int mxs_lradc_probe(struct platform_device *pdev)
{
const struct of_device_id *of_id;
struct device *dev = &pdev->dev;
struct device_node *node = dev->of_node;
struct mxs_lradc *lradc;
struct mfd_cell *cells = NULL;
struct resource *res;
int ret = 0;
u32 ts_wires = 0;
lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
if (!lradc)
return -ENOMEM;
of_id = of_match_device(mxs_lradc_dt_ids, &pdev->dev);
if (!of_id)
return -EINVAL;
lradc->soc = (enum mxs_lradc_id)of_id->data;
lradc->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(lradc->clk)) {
dev_err(dev, "Failed to get the delay unit clock\n");
return PTR_ERR(lradc->clk);
}
ret = clk_prepare_enable(lradc->clk);
if (ret) {
dev_err(dev, "Failed to enable the delay unit clock\n");
return ret;
}
ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
&ts_wires);
if (!ret) {
lradc->buffer_vchans = BUFFER_VCHANS_LIMITED;
switch (ts_wires) {
case 4:
lradc->touchscreen_wire = MXS_LRADC_TOUCHSCREEN_4WIRE;
break;
case 5:
if (lradc->soc == IMX28_LRADC) {
lradc->touchscreen_wire =
MXS_LRADC_TOUCHSCREEN_5WIRE;
break;
}
/* fall through to an error message for i.MX23 */
default:
dev_err(&pdev->dev,
"Unsupported number of touchscreen wires (%d)\n"
, ts_wires);
ret = -EINVAL;
goto err_clk;
}
} else {
lradc->buffer_vchans = BUFFER_VCHANS_ALL;
}
platform_set_drvdata(pdev, lradc);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENOMEM;
switch (lradc->soc) {
case IMX23_LRADC:
mx23_adc_resources[RES_MEM] = *res;
mx23_touchscreen_resources[RES_MEM] = *res;
cells = mx23_cells;
break;
case IMX28_LRADC:
mx28_adc_resources[RES_MEM] = *res;
mx28_touchscreen_resources[RES_MEM] = *res;
cells = mx28_cells;
break;
default:
dev_err(dev, "Unsupported SoC\n");
ret = -ENODEV;
goto err_clk;
}
ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
&cells[ADC_CELL], 1, NULL, 0, NULL);
if (ret) {
dev_err(&pdev->dev, "Failed to add the ADC subdevice\n");
goto err_clk;
}
if (!lradc->touchscreen_wire)
return 0;
ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
&cells[TSC_CELL], 1, NULL, 0, NULL);
if (ret) {
dev_err(&pdev->dev,
"Failed to add the touchscreen subdevice\n");
goto err_clk;
}
return 0;
err_clk:
clk_disable_unprepare(lradc->clk);
return ret;
}
static int mxs_lradc_remove(struct platform_device *pdev)
{
struct mxs_lradc *lradc = platform_get_drvdata(pdev);
clk_disable_unprepare(lradc->clk);
return 0;
}
static struct platform_driver mxs_lradc_driver = {
.driver = {
.name = "mxs-lradc",
.of_match_table = mxs_lradc_dt_ids,
},
.probe = mxs_lradc_probe,
.remove = mxs_lradc_remove,
};
module_platform_driver(mxs_lradc_driver);
MODULE_AUTHOR("Ksenija Stanojevic <ksenija.stanojevic@gmail.com>");
MODULE_DESCRIPTION("Freescale i.MX23/i.MX28 LRADC driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:mxs-lradc");