[PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD
From: Ksenija Stanojevic
Date: Fri Jun 24 2016 - 08:09:33 EST
Add core files for mxs-lradc MFD driver.
Note: this patch won't compile in iio/testing without this patch:
a8f447be8056 ("mfd: Add resource managed APIs for mfd_add_devices")
Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@xxxxxxxxx>
Acked-by: Jonathan Cameron <jic23@xxxxxxxxxx>
---
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 | 217 ++++++++++++++++++++++++++++++++++++++++++
include/linux/mfd/mxs-lradc.h | 204 +++++++++++++++++++++++++++++++++++++++
4 files changed, 439 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 9ca66de..62593ad 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -271,6 +271,23 @@ 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_HI6421_PMIC
tristate "HiSilicon Hi6421 PMU/Codec IC"
depends on OF
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 0f230a6..ecf6399 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -198,3 +198,4 @@ intel-soc-pmic-objs := intel_soc_pmic_core.o intel_soc_pmic_crc.o
intel-soc-pmic-$(CONFIG_INTEL_PMC_IPC) += intel_soc_pmic_bxtwc.o
obj-$(CONFIG_INTEL_SOC_PMIC) += intel-soc-pmic.o
obj-$(CONFIG_MFD_MT6397) += mt6397-core.o
+obj-$(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..d53a524
--- /dev/null
+++ b/drivers/mfd/mxs-lradc.c
@@ -0,0 +1,217 @@
+/*
+ * Freescale MXS LRADC driver
+ *
+ * Copyright (c) 2012 DENX Software Engineering, GmbH.
+ * 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>
+
+static const char * const mx23_lradc_irq_names[] = {
+ "mxs-lradc-touchscreen",
+ "mxs-lradc-channel0",
+ "mxs-lradc-channel1",
+ "mxs-lradc-channel2",
+ "mxs-lradc-channel3",
+ "mxs-lradc-channel4",
+ "mxs-lradc-channel5",
+ "mxs-lradc-channel6",
+ "mxs-lradc-channel7",
+};
+
+static const char * const mx28_lradc_irq_names[] = {
+ "mxs-lradc-touchscreen",
+ "mxs-lradc-thresh0",
+ "mxs-lradc-thresh1",
+ "mxs-lradc-channel0",
+ "mxs-lradc-channel1",
+ "mxs-lradc-channel2",
+ "mxs-lradc-channel3",
+ "mxs-lradc-channel4",
+ "mxs-lradc-channel5",
+ "mxs-lradc-channel6",
+ "mxs-lradc-channel7",
+ "mxs-lradc-button0",
+ "mxs-lradc-button1",
+};
+
+struct mxs_lradc_of_config {
+ const int irq_count;
+ const char * const *irq_name;
+};
+
+static const struct mxs_lradc_of_config mxs_lradc_of_config[] = {
+ [IMX23_LRADC] = {
+ .irq_count = ARRAY_SIZE(mx23_lradc_irq_names),
+ .irq_name = mx23_lradc_irq_names,
+ },
+ [IMX28_LRADC] = {
+ .irq_count = ARRAY_SIZE(mx28_lradc_irq_names),
+ .irq_name = mx28_lradc_irq_names,
+ },
+};
+
+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_add_device(struct platform_device *pdev,
+ struct mxs_lradc *lradc, char *name, int i)
+{
+ struct mfd_cell *cell;
+
+ cell = &lradc->cells[i];
+ cell->name = name;
+ cell->platform_data = lradc;
+ cell->pdata_size = sizeof(*lradc);
+
+ return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, NULL);
+}
+
+static int mxs_lradc_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *of_id =
+ of_match_device(mxs_lradc_dt_ids, &pdev->dev);
+ const struct mxs_lradc_of_config *of_cfg =
+ &mxs_lradc_of_config[(enum mxs_lradc_id)of_id->data];
+ struct device *dev = &pdev->dev;
+ struct device_node *node = dev->of_node;
+ struct mxs_lradc *lradc;
+ struct resource *iores;
+ int ret = 0, touch_ret, i;
+ u32 ts_wires = 0;
+
+ lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
+ if (!lradc)
+ return -ENOMEM;
+ lradc->soc = (enum mxs_lradc_id)of_id->data;
+
+ /* Grab the memory area */
+ iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ lradc->base = devm_ioremap_resource(dev, iores);
+ if (IS_ERR(lradc->base))
+ return PTR_ERR(lradc->base);
+
+ 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 != 0) {
+ dev_err(dev, "Failed to enable the delay unit clock\n");
+ return ret;
+ }
+
+ touch_ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
+ &ts_wires);
+
+ if (touch_ret == 0) {
+ lradc->buffer_vchans = BUFFER_VCHANS_LIMITED;
+ switch (ts_wires) {
+ case 4:
+ lradc->use_touchscreen = MXS_LRADC_TOUCHSCREEN_4WIRE;
+ break;
+ case 5:
+ if (lradc->soc == IMX28_LRADC) {
+ lradc->use_touchscreen =
+ MXS_LRADC_TOUCHSCREEN_5WIRE;
+ break;
+ }
+ /* fall through an error message for i.MX23 */
+ default:
+ dev_err(&pdev->dev,
+ "Unsupported number of touchscreen wires (%d)\n",
+ ts_wires);
+ return -EINVAL;
+ }
+ } else {
+ lradc->buffer_vchans = BUFFER_VCHANS_ALL;
+ }
+
+ lradc->irq_count = of_cfg->irq_count;
+ lradc->irq_name = of_cfg->irq_name;
+ for (i = 0; i < lradc->irq_count; i++) {
+ lradc->irq[i] = platform_get_irq(pdev, i);
+ if (lradc->irq[i] < 0) {
+ ret = lradc->irq[i];
+ goto err_clk;
+ }
+ }
+
+ platform_set_drvdata(pdev, lradc);
+
+ ret = stmp_reset_block(lradc->base);
+ if (ret)
+ return ret;
+
+ ret = mxs_lradc_add_device(pdev, lradc, DRIVER_NAME_ADC, 0);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to add the ADC subdevice\n");
+ goto err_clk;
+ }
+
+ if (!lradc->use_touchscreen)
+ return 0;
+
+ ret = mxs_lradc_add_device(pdev, lradc, DRIVER_NAME_TS, 1);
+ 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..c1475c0
--- /dev/null
+++ b/include/linux/mfd/mxs-lradc.h
@@ -0,0 +1,204 @@
+/*
+ * Freescale MXS LRADC driver
+ *
+ * Copyright (c) 2012 DENX Software Engineering, GmbH.
+ * 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 __MXS_LRADC_H
+#define __MXS_LRADC_H
+
+#include <linux/bitops.h>
+#include <linux/io.h>
+#include <linux/stmp_device.h>
+
+#define DRIVER_NAME_ADC "mxs-lradc-adc"
+#define DRIVER_NAME_TS "mxs-lradc-ts"
+
+#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)
+
+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 {
+ enum mxs_lradc_id soc;
+
+ void __iomem *base;
+ struct clk *clk;
+
+ int irq[13];
+ const char * const *irq_name;
+ int irq_count;
+
+#define BUFFER_VCHANS_LIMITED 0x3f
+#define BUFFER_VCHANS_ALL 0xff
+ u8 buffer_vchans;
+
+ /*
+ * 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_ts_wires use_touchscreen;
+ bool use_touchbutton;
+
+#define MXS_LRADC_CELLS 2
+ struct mfd_cell cells[MXS_LRADC_CELLS];
+};
+
+static inline void mxs_lradc_reg_set(struct mxs_lradc *lradc, u32 val, u32 reg)
+{
+ writel(val, lradc->base + reg + STMP_OFFSET_REG_SET);
+}
+
+static inline void mxs_lradc_reg_clear(struct mxs_lradc *lradc, u32 val,
+ u32 reg)
+{
+ writel(val, lradc->base + reg + STMP_OFFSET_REG_CLR);
+}
+
+static inline void mxs_lradc_reg_wrt(struct mxs_lradc *lradc, u32 val, u32 reg)
+{
+ writel(val, lradc->base + reg);
+}
+
+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;
+ }
+}
+
+#endif /* __MXS_LRADC_H */
--
1.9.1