Re: [PATCH v10 1/5] mfd: mxs-lradc: Add support for mxs-lradc MFD

From: Lee Jones
Date: Mon Nov 21 2016 - 05:46:48 EST


On Sun, 20 Nov 2016, Ksenija Stanojevic wrote:

> Add core files for low resolution analog-to-digital converter (mxs-lradc)
> MFD driver.
>
> Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@xxxxxxxxx>
> ---
> Changes in v10:
> - fetch base address from DT
> - add a NULL check for of_match_device
>
> Changes in v9:
> - improve commit message.
>
> Changes in v8:
> - rebase onto 4.9-rc1
>
> Changes in v7:
> - define macros ADC_CELL and TSC_CELL
> - remove one cell and dynamically set them in the switch()
> - fail in the touchscreen driver instead of mfd driver if
> hardware doesn't contain a touchscreen
>
> Changes in v6:
> - update copyright
> - add kernel-doc header for struct mxs-lradc
> - add error message
> - change EINVAL to ENODEV
> - use PLATFORM_DEVID_NONE instead -1
> - cosmetic fixes
>
> Changes in v5:
> - use DEFINE_RES_MEM
> - don't pass ioreammaped adress to platform cells
> - move comment outside of struct mxs_lradc
> - change type of argument in mxs_lradc_reg_set, mxs_lradc_reg_clear,
> mxs_lradc_reg_wrt (struct mxs_lradc * -> void __iomem *)
>
> Changes in v4:
> - update copyright
> - use DEFINE_RES_IRQ_NAMED
> - remove mxs_lradc_add_device function
> - use struct mfd_cell in static form
> - improve spacing
> - remove unnecessary comment
> - remove platform_get_irq
> - remove touch_ret and use ret instead
> - rename use_touchscreen to touchscreen_wire
> - use goto statements
> - remove irq[13], irq_count and irq_name from struct mxs_lradc
> - remove all defines from inside the struct definition
>
> Changes in v3:
> - add note to commit message
> - move switch statement into if(touch_ret == 0) branch
> - add MODULE_AUTHOR
>
> Changes in v2:
> - do not change spacing in Kconfig
> - make struct mfd_cell part of struct mxs_lradc
> - use switch instead of if in mxs_lradc_irq_mask
> - use only necessary header files in mxs_lradc.h
> - use devm_mfd_add_device
> - use separate function to register mfd device
> - change licence to GPL
> - add copyright
>
> drivers/mfd/Kconfig | 17 +++
> drivers/mfd/Makefile | 1 +
> drivers/mfd/mxs-lradc.c | 261 ++++++++++++++++++++++++++++++++++++++++++
> include/linux/mfd/mxs-lradc.h | 203 ++++++++++++++++++++++++++++++++
> 4 files changed, 482 insertions(+)
> create mode 100644 drivers/mfd/mxs-lradc.c
> create mode 100644 include/linux/mfd/mxs-lradc.h
>
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 819dc0a..e5c1289 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -343,6 +343,23 @@ config MFD_MC13XXX_I2C
> help
> Select this if your MC13xxx is connected via an I2C bus.
>
> +config MFD_MXS_LRADC
> + tristate "Freescale i.MX23/i.MX28 LRADC"
> + depends on ARCH_MXS || COMPILE_TEST
> + select MFD_CORE
> + select STMP_DEVICE
> + help
> + Say yes here to build support for the Low Resolution
> + Analog-to-Digital Converter (LRADC) found on the i.MX23 and i.MX28
> + processors. This driver provides common support for accessing the
> + device, additional drivers must be enabled in order to use the
> + functionality of the device:
> + mxs-lradc-adc for ADC readings
> + mxs-lradc-ts for touchscreen support
> +
> + This driver can also be built as a module. If so, the module will be
> + called mxs-lradc.
> +
> config MFD_MX25_TSADC
> tristate "Freescale i.MX25 integrated Touchscreen and ADC unit"
> select REGMAP_MMIO
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index db39377..90e9f36 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -212,3 +212,4 @@ obj-$(CONFIG_MFD_MT6397) += mt6397-core.o
>
> obj-$(CONFIG_MFD_ALTERA_A10SR) += altera-a10sr.o
> obj-$(CONFIG_MFD_SUN4I_GPADC) += sun4i-gpadc.o
> +obj-$(CONFIG_MFD_MXS_LRADC) += mxs-lradc.o
> diff --git a/drivers/mfd/mxs-lradc.c b/drivers/mfd/mxs-lradc.c
> new file mode 100644
> index 0000000..8f56cf9
> --- /dev/null
> +++ b/drivers/mfd/mxs-lradc.c
> @@ -0,0 +1,261 @@
> +/*
> + * Freescale MXS Low Resolution Analog-to-Digital Converter driver
> + *
> + * Copyright (c) 2012 DENX Software Engineering, GmbH.
> + * Copyright (c) 2016 Ksenija Stanojevic <ksenija.stanojevic@xxxxxxxxx>
> + *
> + * Authors:
> + * Marek Vasut <marex@xxxxxxx>
> + * Ksenija Stanojevic <ksenija.stanojevic@xxxxxxxxx>
> + *
> + * 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 mxs_cells[] = {
> + {
> + .name = "mxs-lradc-adc",
> + },
> + {
> + .name = "mxs-lradc-ts",
> + },
> +};
> +
> +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 = mxs_cells;
> + 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[ADC_CELL].resources = mx23_adc_resources;
> + cells[ADC_CELL].num_resources = ARRAY_SIZE(mx23_adc_resources);
> + cells[TSC_CELL].resources = mx23_touchscreen_resources;
> + cells[TSC_CELL].num_resources =
> + ARRAY_SIZE(mx23_touchscreen_resources);
> + break;
> + case IMX28_LRADC:
> + mx28_adc_resources[0] = *res;
> + mx28_touchscreen_resources[0] = *res;
> + cells[ADC_CELL].resources = mx28_adc_resources;
> + cells[ADC_CELL].num_resources = ARRAY_SIZE(mx28_adc_resources);
> + cells[TSC_CELL].resources = mx28_touchscreen_resources;
> + cells[TSC_CELL].num_resources =
> + ARRAY_SIZE(mx28_touchscreen_resources);
> + break;

You only need to do this if some parts of the cells are dynamically
obtained. All of these resources are static, so just create static
'struct mfd_cell's like most other drivers do.

> + default:
> + dev_err(dev, "Unsupported SoC\n");
> + ret = -ENODEV;
> + goto err_clk;
> + }
> +
> + cells[ADC_CELL].platform_data = lradc;
> + cells[ADC_CELL].pdata_size = sizeof(*lradc);

This isn't platform data either, it's driver data. Use the
platform_set_drvdata() API for this.

> + 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;
> + }
> +
> + cells[TSC_CELL].platform_data = lradc;
> + cells[TSC_CELL].pdata_size = sizeof(*lradc);

Same here.

> + 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@xxxxxxxxx>");
> +MODULE_DESCRIPTION("Freescale i.MX23/i.MX28 LRADC driver");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:mxs-lradc");
> diff --git a/include/linux/mfd/mxs-lradc.h b/include/linux/mfd/mxs-lradc.h
> new file mode 100644
> index 0000000..64140681
> --- /dev/null
> +++ b/include/linux/mfd/mxs-lradc.h
> @@ -0,0 +1,203 @@
> +/*
> + * Freescale MXS Low Resolution Analog-to-Digital Converter driver
> + *
> + * Copyright (c) 2012 DENX Software Engineering, GmbH.
> + * Copyright (c) 2016 Ksenija Stanojevic <ksenija.stanojevic@xxxxxxxxx>
> + *
> + * Author: Marek Vasut <marex@xxxxxxx>
> + *
> + * 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.
> + */
> +
> +#ifndef __MFD_MXS_LRADC_H
> +#define __MFD_MXS_LRADC_H
> +
> +#include <linux/bitops.h>
> +#include <linux/io.h>
> +#include <linux/stmp_device.h>
> +
> +#define LRADC_MAX_DELAY_CHANS 4
> +#define LRADC_MAX_MAPPED_CHANS 8
> +#define LRADC_MAX_TOTAL_CHANS 16
> +
> +#define LRADC_DELAY_TIMER_HZ 2000
> +
> +#define LRADC_CTRL0 0x00
> +# define LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE BIT(23)
> +# define LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE BIT(22)
> +# define LRADC_CTRL0_MX28_YNNSW /* YM */ BIT(21)
> +# define LRADC_CTRL0_MX28_YPNSW /* YP */ BIT(20)
> +# define LRADC_CTRL0_MX28_YPPSW /* YP */ BIT(19)
> +# define LRADC_CTRL0_MX28_XNNSW /* XM */ BIT(18)
> +# define LRADC_CTRL0_MX28_XNPSW /* XM */ BIT(17)
> +# define LRADC_CTRL0_MX28_XPPSW /* XP */ BIT(16)
> +
> +# define LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE BIT(20)
> +# define LRADC_CTRL0_MX23_YM BIT(19)
> +# define LRADC_CTRL0_MX23_XM BIT(18)
> +# define LRADC_CTRL0_MX23_YP BIT(17)
> +# define LRADC_CTRL0_MX23_XP BIT(16)
> +
> +# define LRADC_CTRL0_MX28_PLATE_MASK \
> + (LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE | \
> + LRADC_CTRL0_MX28_YNNSW | LRADC_CTRL0_MX28_YPNSW | \
> + LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW | \
> + LRADC_CTRL0_MX28_XNPSW | LRADC_CTRL0_MX28_XPPSW)
> +
> +# define LRADC_CTRL0_MX23_PLATE_MASK \
> + (LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE | \
> + LRADC_CTRL0_MX23_YM | LRADC_CTRL0_MX23_XM | \
> + LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XP)
> +
> +#define LRADC_CTRL1 0x10
> +#define LRADC_CTRL1_TOUCH_DETECT_IRQ_EN BIT(24)
> +#define LRADC_CTRL1_LRADC_IRQ_EN(n) (1 << ((n) + 16))
> +#define LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK (0x1fff << 16)
> +#define LRADC_CTRL1_MX23_LRADC_IRQ_EN_MASK (0x01ff << 16)
> +#define LRADC_CTRL1_LRADC_IRQ_EN_OFFSET 16
> +#define LRADC_CTRL1_TOUCH_DETECT_IRQ BIT(8)
> +#define LRADC_CTRL1_LRADC_IRQ(n) (1 << (n))
> +#define LRADC_CTRL1_MX28_LRADC_IRQ_MASK 0x1fff
> +#define LRADC_CTRL1_MX23_LRADC_IRQ_MASK 0x01ff
> +#define LRADC_CTRL1_LRADC_IRQ_OFFSET 0
> +
> +#define LRADC_CTRL2 0x20
> +#define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET 24
> +#define LRADC_CTRL2_TEMPSENSE_PWD BIT(15)
> +
> +#define LRADC_STATUS 0x40
> +#define LRADC_STATUS_TOUCH_DETECT_RAW BIT(0)
> +
> +#define LRADC_CH(n) (0x50 + (0x10 * (n)))
> +#define LRADC_CH_ACCUMULATE BIT(29)
> +#define LRADC_CH_NUM_SAMPLES_MASK (0x1f << 24)
> +#define LRADC_CH_NUM_SAMPLES_OFFSET 24
> +#define LRADC_CH_NUM_SAMPLES(x) \
> + ((x) << LRADC_CH_NUM_SAMPLES_OFFSET)
> +#define LRADC_CH_VALUE_MASK 0x3ffff
> +#define LRADC_CH_VALUE_OFFSET 0
> +
> +#define LRADC_DELAY(n) (0xd0 + (0x10 * (n)))
> +#define LRADC_DELAY_TRIGGER_LRADCS_MASK (0xffUL << 24)
> +#define LRADC_DELAY_TRIGGER_LRADCS_OFFSET 24
> +#define LRADC_DELAY_TRIGGER(x) \
> + (((x) << LRADC_DELAY_TRIGGER_LRADCS_OFFSET) & \
> + LRADC_DELAY_TRIGGER_LRADCS_MASK)
> +#define LRADC_DELAY_KICK BIT(20)
> +#define LRADC_DELAY_TRIGGER_DELAYS_MASK (0xf << 16)
> +#define LRADC_DELAY_TRIGGER_DELAYS_OFFSET 16
> +#define LRADC_DELAY_TRIGGER_DELAYS(x) \
> + (((x) << LRADC_DELAY_TRIGGER_DELAYS_OFFSET) & \
> + LRADC_DELAY_TRIGGER_DELAYS_MASK)
> +#define LRADC_DELAY_LOOP_COUNT_MASK (0x1f << 11)
> +#define LRADC_DELAY_LOOP_COUNT_OFFSET 11
> +#define LRADC_DELAY_LOOP(x) \
> + (((x) << LRADC_DELAY_LOOP_COUNT_OFFSET) & \
> + LRADC_DELAY_LOOP_COUNT_MASK)
> +#define LRADC_DELAY_DELAY_MASK 0x7ff
> +#define LRADC_DELAY_DELAY_OFFSET 0
> +#define LRADC_DELAY_DELAY(x) \
> + (((x) << LRADC_DELAY_DELAY_OFFSET) & \
> + LRADC_DELAY_DELAY_MASK)
> +
> +#define LRADC_CTRL4 0x140
> +#define LRADC_CTRL4_LRADCSELECT_MASK(n) (0xf << ((n) * 4))
> +#define LRADC_CTRL4_LRADCSELECT_OFFSET(n) ((n) * 4)
> +#define LRADC_CTRL4_LRADCSELECT(n, x) \
> + (((x) << LRADC_CTRL4_LRADCSELECT_OFFSET(n)) & \
> + LRADC_CTRL4_LRADCSELECT_MASK(n))
> +
> +#define LRADC_RESOLUTION 12
> +#define LRADC_SINGLE_SAMPLE_MASK ((1 << LRADC_RESOLUTION) - 1)
> +
> +#define BUFFER_VCHANS_LIMITED 0x3f
> +#define BUFFER_VCHANS_ALL 0xff
> +
> + /*
> + * Certain LRADC channels are shared between touchscreen
> + * and/or touch-buttons and generic LRADC block. Therefore when using
> + * either of these, these channels are not available for the regular
> + * sampling. The shared channels are as follows:
> + *
> + * CH0 -- Touch button #0
> + * CH1 -- Touch button #1
> + * CH2 -- Touch screen XPUL
> + * CH3 -- Touch screen YPLL
> + * CH4 -- Touch screen XNUL
> + * CH5 -- Touch screen YNLR
> + * CH6 -- Touch screen WIPER (5-wire only)
> + *
> + * The bit fields below represents which parts of the LRADC block are
> + * switched into special mode of operation. These channels can not
> + * be sampled as regular LRADC channels. The driver will refuse any
> + * attempt to sample these channels.
> + */
> +#define CHAN_MASK_TOUCHBUTTON (BIT(1) | BIT(0))
> +#define CHAN_MASK_TOUCHSCREEN_4WIRE (0xf << 2)
> +#define CHAN_MASK_TOUCHSCREEN_5WIRE (0x1f << 2)
> +
> +enum mxs_lradc_id {
> + IMX23_LRADC,
> + IMX28_LRADC,
> +};
> +
> +enum mxs_lradc_ts_wires {
> + MXS_LRADC_TOUCHSCREEN_NONE = 0,
> + MXS_LRADC_TOUCHSCREEN_4WIRE,
> + MXS_LRADC_TOUCHSCREEN_5WIRE,
> +};
> +
> +/**
> + * struct mxs_lradc
> + * @soc: soc type (IMX23 or IMX28)
> + * @clk: 2 kHz clock for delay units
> + * @buffer_vchans: channels that can be used during buffered capture
> + * @touchscreen_wire: touchscreen type (4-wire or 5-wire)
> + * @use_touchbutton: button state (on or off)
> + */
> +struct mxs_lradc {
> + enum mxs_lradc_id soc;
> + struct clk *clk;
> + u8 buffer_vchans;
> +
> + enum mxs_lradc_ts_wires touchscreen_wire;
> + bool use_touchbutton;
> +};
> +
> +static inline void mxs_lradc_reg_set(void __iomem *base, u32 val, u32 reg)
> +{
> + writel(val, base + reg + STMP_OFFSET_REG_SET);
> +}
> +
> +static inline void mxs_lradc_reg_clear(void __iomem *base, u32 val,
> + u32 reg)
> +{
> + writel(val, base + reg + STMP_OFFSET_REG_CLR);
> +}
> +
> +static inline void mxs_lradc_reg_wrt(void __iomem *base, u32 val, u32 reg)
> +{
> + writel(val, base + reg);
> +}

This type of API is pointless. Just use the writel() functions
directly.

> +static inline u32 mxs_lradc_irq_mask(struct mxs_lradc *lradc)
> +{
> + switch (lradc->soc) {
> + case IMX23_LRADC:
> + return LRADC_CTRL1_MX23_LRADC_IRQ_MASK;
> + case IMX28_LRADC:
> + return LRADC_CTRL1_MX28_LRADC_IRQ_MASK;
> + default:
> + return 0;
> + }
> +}

Use these directly too.

> +#endif /* __MXS_LRADC_H */

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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