[PATCH v8 4/8] mfd: fsl imx25 Touchscreen ADC driver
Jonathan Cameron
jic23 at kernel.org
Sat Nov 21 09:02:34 PST 2015
On 16/11/15 12:01, Markus Pargmann wrote:
> This is the core driver for imx25 touchscreen/adc driver. The module
> has one shared ADC and two different conversion queues which use the
> ADC. The two queues are identical. Both can be used for general purpose
> ADC but one is meant to be used for touchscreens.
>
> This driver is the core which manages the central components and
> registers of the TSC/ADC unit. It manages the IRQs and forwards them to
> the correct components.
>
> Signed-off-by: Markus Pargmann <mpa at pengutronix.de>
> Signed-off-by: Denis Carikli <denis at eukrea.com>
>
> [ensure correct ADC clock depending on the IPG clock]
> Signed-off-by: Juergen Borleis <jbe at pengutronix.de>
Looks good to me - one query on meaning of a comment inline.
Acked-by: Jonathan Cameron <jic23 at kernel.org>
I'm taking the view this series wants to go through the MFD tree
but don't mind if it goes through IIO or input instead
if there is a good reason to do so.
Jonathan
> ---
>
> Notes:
> Changes in v7:
> - Cleanup bit defines in header files to be more readable
> - Fix irq check to return with an error for irq <= 0
> - Add COMPILE_TEST in Kconfig file
>
> Changes in v5:
> - Remove ifdef CONFIG_OF as this driver is only for DT usage
> - Remove module owner
> - Add Kconfig dependencies ARCH_MX25 and OF
>
> @Jonathan Cameron:
> I left your acked-by on the patch as these were small changes. If it should be
> removed, please say so. Thanks
>
> drivers/mfd/Kconfig | 9 ++
> drivers/mfd/Makefile | 2 +
> drivers/mfd/fsl-imx25-tsadc.c | 204 ++++++++++++++++++++++++++++++++++++++++
> include/linux/mfd/imx25-tsadc.h | 140 +++++++++++++++++++++++++++
> 4 files changed, 355 insertions(+)
> create mode 100644 drivers/mfd/fsl-imx25-tsadc.c
> create mode 100644 include/linux/mfd/imx25-tsadc.h
>
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 4d92df6ef9fe..4222e202ad2b 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -271,6 +271,15 @@ config MFD_MC13XXX_I2C
> help
> Select this if your MC13xxx is connected via an I2C bus.
>
> +config MFD_MX25_TSADC
> + tristate "Freescale i.MX25 integrated Touchscreen and ADC unit"
> + select REGMAP_MMIO
> + depends on (SOC_IMX25 && OF) || COMPILE_TEST
> + help
> + Enable support for the integrated Touchscreen and ADC unit of the
> + i.MX25 processors. They consist of a conversion queue for general
> + purpose ADC and a queue for Touchscreens.
> +
> config MFD_HI6421_PMIC
> tristate "HiSilicon Hi6421 PMU/Codec IC"
> depends on OF
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index a8b76b81b467..5741be88c173 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -81,6 +81,8 @@ obj-$(CONFIG_TWL4030_POWER) += twl4030-power.o
> obj-$(CONFIG_MFD_TWL4030_AUDIO) += twl4030-audio.o
> obj-$(CONFIG_TWL6040_CORE) += twl6040.o
>
> +obj-$(CONFIG_MFD_MX25_TSADC) += fsl-imx25-tsadc.o
> +
> obj-$(CONFIG_MFD_MC13XXX) += mc13xxx-core.o
> obj-$(CONFIG_MFD_MC13XXX_SPI) += mc13xxx-spi.o
> obj-$(CONFIG_MFD_MC13XXX_I2C) += mc13xxx-i2c.o
> diff --git a/drivers/mfd/fsl-imx25-tsadc.c b/drivers/mfd/fsl-imx25-tsadc.c
> new file mode 100644
> index 000000000000..e67d5ca81e10
> --- /dev/null
> +++ b/drivers/mfd/fsl-imx25-tsadc.c
> @@ -0,0 +1,204 @@
> +/*
> + * Copyright (C) 2014-2015 Pengutronix, Markus Pargmann <mpa at pengutronix.de>
> + *
> + * This program is free software; you can redistribute it and/or modify it under
> + * the terms of the GNU General Public License version 2 as published by the
> + * Free Software Foundation.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/interrupt.h>
> +#include <linux/irqchip/chained_irq.h>
> +#include <linux/irqdesc.h>
> +#include <linux/irqdomain.h>
> +#include <linux/irq.h>
> +#include <linux/mfd/imx25-tsadc.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +
> +static struct regmap_config mx25_tsadc_regmap_config = {
> + .fast_io = true,
> + .max_register = 8,
> + .reg_bits = 32,
> + .val_bits = 32,
> + .reg_stride = 4,
> +};
> +
> +static void mx25_tsadc_irq_handler(struct irq_desc *desc)
> +{
> + struct mx25_tsadc *tsadc = irq_desc_get_handler_data(desc);
> + struct irq_chip *chip = irq_desc_get_chip(desc);
> + u32 status;
> +
> + chained_irq_enter(chip, desc);
> +
> + regmap_read(tsadc->regs, MX25_TSC_TGSR, &status);
> +
> + if (status & MX25_TGSR_GCQ_INT)
> + generic_handle_irq(irq_find_mapping(tsadc->domain, 1));
> +
> + if (status & MX25_TGSR_TCQ_INT)
> + generic_handle_irq(irq_find_mapping(tsadc->domain, 0));
> +
> + chained_irq_exit(chip, desc);
> +}
> +
> +static int mx25_tsadc_domain_map(struct irq_domain *d, unsigned int irq,
> + irq_hw_number_t hwirq)
> +{
> + struct mx25_tsadc *tsadc = d->host_data;
> +
> + irq_set_chip_data(irq, tsadc);
> + irq_set_chip_and_handler(irq, &dummy_irq_chip,
> + handle_level_irq);
> + irq_modify_status(irq, IRQ_NOREQUEST, IRQ_NOPROBE);
> +
> + return 0;
> +}
> +
> +static struct irq_domain_ops mx25_tsadc_domain_ops = {
> + .map = mx25_tsadc_domain_map,
> + .xlate = irq_domain_xlate_onecell,
> +};
> +
> +static int mx25_tsadc_setup_irq(struct platform_device *pdev,
> + struct mx25_tsadc *tsadc)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *np = dev->of_node;
> + int irq;
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq <= 0) {
> + dev_err(dev, "Failed to get irq\n");
> + return irq;
> + }
> +
> + tsadc->domain = irq_domain_add_simple(np, 2, 0, &mx25_tsadc_domain_ops,
> + tsadc);
> + if (!tsadc->domain) {
> + dev_err(dev, "Failed to add irq domain\n");
> + return -ENOMEM;
> + }
> +
> + irq_set_chained_handler(irq, mx25_tsadc_irq_handler);
> + irq_set_handler_data(irq, tsadc);
> +
> + return 0;
> +}
> +
> +static void mx25_tsadc_setup_clk(struct platform_device *pdev,
> + struct mx25_tsadc *tsadc)
> +{
> + unsigned clk_div;
> +
> + /*
> + * According to the datasheet the ADC clock should never
> + * exceed 1,75 MHz. Base clock is the IPG and the ADC unit uses
> + * a funny clock divider. To keep the time constant the ADC needs to do
> + * one conversion, adapt the ADC internal clock divider to
> + * the available IPG
I'm not entirely following this explanation...
maybe
...one conversion, then adapt the ADC...
> + */
> +
> + dev_dbg(&pdev->dev, "Found master clock at %lu Hz\n",
> + clk_get_rate(tsadc->clk));
> +
> + clk_div = DIV_ROUND_UP(clk_get_rate(tsadc->clk), 1750000);
> + dev_dbg(&pdev->dev, "Setting up ADC clock divider to %u\n", clk_div);
> +
> + /* adc clock = IPG clock / (2 * div + 2) */
> + clk_div -= 2;
> + clk_div /= 2;
> +
> + /*
> + * the ADC clock divider changes its behaviour when values below 4
> + * are used: it is fixed to "/ 10" in this case
> + */
> + clk_div = max_t(unsigned, 4, clk_div);
> +
> + dev_dbg(&pdev->dev, "Resulting ADC conversion clock at %lu Hz\n",
> + clk_get_rate(tsadc->clk) / (2 * clk_div + 2));
> +
> + regmap_update_bits(tsadc->regs, MX25_TSC_TGCR,
> + MX25_TGCR_ADCCLKCFG(0x1f),
> + MX25_TGCR_ADCCLKCFG(clk_div));
> +}
> +
> +static int mx25_tsadc_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *np = dev->of_node;
> + struct mx25_tsadc *tsadc;
> + struct resource *res;
> + int ret;
> + void __iomem *iomem;
> +
> + tsadc = devm_kzalloc(dev, sizeof(*tsadc), GFP_KERNEL);
> + if (!tsadc)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + iomem = devm_ioremap_resource(dev, res);
> + if (IS_ERR(iomem))
> + return PTR_ERR(iomem);
> +
> + tsadc->regs = devm_regmap_init_mmio(dev, iomem,
> + &mx25_tsadc_regmap_config);
> + if (IS_ERR(tsadc->regs)) {
> + dev_err(dev, "Failed to initialize regmap\n");
> + return PTR_ERR(tsadc->regs);
> + }
> +
> + tsadc->clk = devm_clk_get(dev, "ipg");
> + if (IS_ERR(tsadc->clk)) {
> + dev_err(dev, "Failed to get ipg clock\n");
> + return PTR_ERR(tsadc->clk);
> + }
> +
> + /* setup clock according to the datasheet */
> + mx25_tsadc_setup_clk(pdev, tsadc);
> +
> + /* Enable clock and reset the component */
> + regmap_update_bits(tsadc->regs, MX25_TSC_TGCR, MX25_TGCR_CLK_EN,
> + MX25_TGCR_CLK_EN);
> + regmap_update_bits(tsadc->regs, MX25_TSC_TGCR, MX25_TGCR_TSC_RST,
> + MX25_TGCR_TSC_RST);
> +
> + /* Setup powersaving mode, but enable internal reference voltage */
> + regmap_update_bits(tsadc->regs, MX25_TSC_TGCR, MX25_TGCR_POWERMODE_MASK,
> + MX25_TGCR_POWERMODE_SAVE);
> + regmap_update_bits(tsadc->regs, MX25_TSC_TGCR, MX25_TGCR_INTREFEN,
> + MX25_TGCR_INTREFEN);
> +
> + ret = mx25_tsadc_setup_irq(pdev, tsadc);
> + if (ret)
> + return ret;
> +
> + platform_set_drvdata(pdev, tsadc);
> +
> + of_platform_populate(np, NULL, NULL, dev);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id mx25_tsadc_ids[] = {
> + { .compatible = "fsl,imx25-tsadc" },
> + { /* Sentinel */ }
> +};
> +
> +static struct platform_driver mx25_tsadc_driver = {
> + .driver = {
> + .name = "mx25-tsadc",
> + .of_match_table = of_match_ptr(mx25_tsadc_ids),
> + },
> + .probe = mx25_tsadc_probe,
> +};
> +module_platform_driver(mx25_tsadc_driver);
> +
> +MODULE_DESCRIPTION("MFD for ADC/TSC for Freescale mx25");
> +MODULE_AUTHOR("Markus Pargmann <mpa at pengutronix.de>");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform:mx25-tsadc");
> diff --git a/include/linux/mfd/imx25-tsadc.h b/include/linux/mfd/imx25-tsadc.h
> new file mode 100644
> index 000000000000..7fe4b8c3baac
> --- /dev/null
> +++ b/include/linux/mfd/imx25-tsadc.h
> @@ -0,0 +1,140 @@
> +#ifndef _LINUX_INCLUDE_MFD_IMX25_TSADC_H_
> +#define _LINUX_INCLUDE_MFD_IMX25_TSADC_H_
> +
> +struct regmap;
> +struct clk;
> +
> +struct mx25_tsadc {
> + struct regmap *regs;
> + struct irq_domain *domain;
> + struct clk *clk;
> +};
> +
> +#define MX25_TSC_TGCR 0x00
> +#define MX25_TSC_TGSR 0x04
> +#define MX25_TSC_TICR 0x08
> +
> +/* The same register layout for TC and GC queue */
> +#define MX25_ADCQ_FIFO 0x00
> +#define MX25_ADCQ_CR 0x04
> +#define MX25_ADCQ_SR 0x08
> +#define MX25_ADCQ_MR 0x0c
> +#define MX25_ADCQ_ITEM_7_0 0x20
> +#define MX25_ADCQ_ITEM_15_8 0x24
> +#define MX25_ADCQ_CFG(n) (0x40 + ((n) * 0x4))
> +
> +#define MX25_ADCQ_MR_MASK 0xffffffff
> +
> +/* TGCR */
> +#define MX25_TGCR_PDBTIME(x) ((x) << 25)
> +#define MX25_TGCR_PDBTIME_MASK GENMASK(31, 25)
> +#define MX25_TGCR_PDBEN BIT(24)
> +#define MX25_TGCR_PDEN BIT(23)
> +#define MX25_TGCR_ADCCLKCFG(x) ((x) << 16)
> +#define MX25_TGCR_GET_ADCCLK(x) (((x) >> 16) & 0x1f)
> +#define MX25_TGCR_INTREFEN BIT(10)
> +#define MX25_TGCR_POWERMODE_MASK GENMASK(9, 8)
> +#define MX25_TGCR_POWERMODE_SAVE (1 << 8)
> +#define MX25_TGCR_POWERMODE_ON (2 << 8)
> +#define MX25_TGCR_STLC BIT(5)
> +#define MX25_TGCR_SLPC BIT(4)
> +#define MX25_TGCR_FUNC_RST BIT(2)
> +#define MX25_TGCR_TSC_RST BIT(1)
> +#define MX25_TGCR_CLK_EN BIT(0)
> +
> +/* TGSR */
> +#define MX25_TGSR_SLP_INT BIT(2)
> +#define MX25_TGSR_GCQ_INT BIT(1)
> +#define MX25_TGSR_TCQ_INT BIT(0)
> +
> +/* ADCQ_ITEM_* */
> +#define _MX25_ADCQ_ITEM(item, x) ((x) << ((item) * 4))
> +#define MX25_ADCQ_ITEM(item, x) ((item) >= 8 ? \
> + _MX25_ADCQ_ITEM((item) - 8, (x)) : _MX25_ADCQ_ITEM((item), (x)))
> +
> +/* ADCQ_FIFO (TCQFIFO and GCQFIFO) */
> +#define MX25_ADCQ_FIFO_DATA(x) (((x) >> 4) & 0xfff)
> +#define MX25_ADCQ_FIFO_ID(x) ((x) & 0xf)
> +
> +/* ADCQ_CR (TCQR and GCQR) */
> +#define MX25_ADCQ_CR_PDCFG_LEVEL BIT(19)
> +#define MX25_ADCQ_CR_PDMSK BIT(18)
> +#define MX25_ADCQ_CR_FRST BIT(17)
> +#define MX25_ADCQ_CR_QRST BIT(16)
> +#define MX25_ADCQ_CR_RWAIT_MASK GENMASK(15, 12)
> +#define MX25_ADCQ_CR_RWAIT(x) ((x) << 12)
> +#define MX25_ADCQ_CR_WMRK_MASK GENMASK(11, 8)
> +#define MX25_ADCQ_CR_WMRK(x) ((x) << 8)
> +#define MX25_ADCQ_CR_LITEMID_MASK (0xf << 4)
> +#define MX25_ADCQ_CR_LITEMID(x) ((x) << 4)
> +#define MX25_ADCQ_CR_RPT BIT(3)
> +#define MX25_ADCQ_CR_FQS BIT(2)
> +#define MX25_ADCQ_CR_QSM_MASK GENMASK(1, 0)
> +#define MX25_ADCQ_CR_QSM_PD 0x1
> +#define MX25_ADCQ_CR_QSM_FQS 0x2
> +#define MX25_ADCQ_CR_QSM_FQS_PD 0x3
> +
> +/* ADCQ_SR (TCQSR and GCQSR) */
> +#define MX25_ADCQ_SR_FDRY BIT(15)
> +#define MX25_ADCQ_SR_FULL BIT(14)
> +#define MX25_ADCQ_SR_EMPT BIT(13)
> +#define MX25_ADCQ_SR_FDN(x) (((x) >> 8) & 0x1f)
> +#define MX25_ADCQ_SR_FRR BIT(6)
> +#define MX25_ADCQ_SR_FUR BIT(5)
> +#define MX25_ADCQ_SR_FOR BIT(4)
> +#define MX25_ADCQ_SR_EOQ BIT(1)
> +#define MX25_ADCQ_SR_PD BIT(0)
> +
> +/* ADCQ_MR (TCQMR and GCQMR) */
> +#define MX25_ADCQ_MR_FDRY_DMA BIT(31)
> +#define MX25_ADCQ_MR_FER_DMA BIT(22)
> +#define MX25_ADCQ_MR_FUR_DMA BIT(21)
> +#define MX25_ADCQ_MR_FOR_DMA BIT(20)
> +#define MX25_ADCQ_MR_EOQ_DMA BIT(17)
> +#define MX25_ADCQ_MR_PD_DMA BIT(16)
> +#define MX25_ADCQ_MR_FDRY_IRQ BIT(15)
> +#define MX25_ADCQ_MR_FER_IRQ BIT(6)
> +#define MX25_ADCQ_MR_FUR_IRQ BIT(5)
> +#define MX25_ADCQ_MR_FOR_IRQ BIT(4)
> +#define MX25_ADCQ_MR_EOQ_IRQ BIT(1)
> +#define MX25_ADCQ_MR_PD_IRQ BIT(0)
> +
> +/* ADCQ_CFG (TICR, TCC0-7,GCC0-7) */
> +#define MX25_ADCQ_CFG_SETTLING_TIME(x) ((x) << 24)
> +#define MX25_ADCQ_CFG_IGS (1 << 20)
> +#define MX25_ADCQ_CFG_NOS_MASK GENMASK(19, 16)
> +#define MX25_ADCQ_CFG_NOS(x) (((x) - 1) << 16)
> +#define MX25_ADCQ_CFG_WIPER (1 << 15)
> +#define MX25_ADCQ_CFG_YNLR (1 << 14)
> +#define MX25_ADCQ_CFG_YPLL_HIGH (0 << 12)
> +#define MX25_ADCQ_CFG_YPLL_OFF (1 << 12)
> +#define MX25_ADCQ_CFG_YPLL_LOW (3 << 12)
> +#define MX25_ADCQ_CFG_XNUR_HIGH (0 << 10)
> +#define MX25_ADCQ_CFG_XNUR_OFF (1 << 10)
> +#define MX25_ADCQ_CFG_XNUR_LOW (3 << 10)
> +#define MX25_ADCQ_CFG_XPUL_HIGH (0 << 9)
> +#define MX25_ADCQ_CFG_XPUL_OFF (1 << 9)
> +#define MX25_ADCQ_CFG_REFP(sel) ((sel) << 7)
> +#define MX25_ADCQ_CFG_REFP_YP MX25_ADCQ_CFG_REFP(0)
> +#define MX25_ADCQ_CFG_REFP_XP MX25_ADCQ_CFG_REFP(1)
> +#define MX25_ADCQ_CFG_REFP_EXT MX25_ADCQ_CFG_REFP(2)
> +#define MX25_ADCQ_CFG_REFP_INT MX25_ADCQ_CFG_REFP(3)
> +#define MX25_ADCQ_CFG_REFP_MASK GENMASK(8, 7)
> +#define MX25_ADCQ_CFG_IN(sel) ((sel) << 4)
> +#define MX25_ADCQ_CFG_IN_XP MX25_ADCQ_CFG_IN(0)
> +#define MX25_ADCQ_CFG_IN_YP MX25_ADCQ_CFG_IN(1)
> +#define MX25_ADCQ_CFG_IN_XN MX25_ADCQ_CFG_IN(2)
> +#define MX25_ADCQ_CFG_IN_YN MX25_ADCQ_CFG_IN(3)
> +#define MX25_ADCQ_CFG_IN_WIPER MX25_ADCQ_CFG_IN(4)
> +#define MX25_ADCQ_CFG_IN_AUX0 MX25_ADCQ_CFG_IN(5)
> +#define MX25_ADCQ_CFG_IN_AUX1 MX25_ADCQ_CFG_IN(6)
> +#define MX25_ADCQ_CFG_IN_AUX2 MX25_ADCQ_CFG_IN(7)
> +#define MX25_ADCQ_CFG_REFN(sel) ((sel) << 2)
> +#define MX25_ADCQ_CFG_REFN_XN MX25_ADCQ_CFG_REFN(0)
> +#define MX25_ADCQ_CFG_REFN_YN MX25_ADCQ_CFG_REFN(1)
> +#define MX25_ADCQ_CFG_REFN_NGND MX25_ADCQ_CFG_REFN(2)
> +#define MX25_ADCQ_CFG_REFN_NGND2 MX25_ADCQ_CFG_REFN(3)
> +#define MX25_ADCQ_CFG_REFN_MASK GENMASK(3, 2)
> +#define MX25_ADCQ_CFG_PENIACK (1 << 1)
> +
> +#endif /* _LINUX_INCLUDE_MFD_IMX25_TSADC_H_ */
>
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