[PATCH 3/4] input: Add new sun4i-keypad driver
Maxime Ripard
maxime.ripard at free-electrons.com
Thu Sep 17 06:05:20 PDT 2015
Hi,
On Wed, Sep 16, 2015 at 12:05:56AM +1000, yassinjaffer at gmail.com wrote:
> From: Yassin Jaffer <yassinjaffer at gmail.com>
>
> Allwinnner SUN4i Keypad controller is used to interface a SoC
> with a matrix-typekeypad device.
> The keypad controller supports multiple row and column lines.
> A key can be placed at each intersection of a unique
> row and a unique column.
> The keypad controller can sense a key-press and key-release and report the
> event using a interrupt to the cpu.
> This patch adds a driver support to this.
> The keypad controller driver does not give proper information
> if more that two keys are selected.
>
> Signed-off-by: Yassin Jaffer <yassinjaffer at gmail.com>
> ---
> drivers/input/keyboard/Kconfig | 11 ++
> drivers/input/keyboard/Makefile | 1 +
> drivers/input/keyboard/sun4i-keypad.c | 361 ++++++++++++++++++++++++++++++++++
> 3 files changed, 373 insertions(+)
> create mode 100644 drivers/input/keyboard/sun4i-keypad.c
>
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index 2e80107..4f2f3f8 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -590,6 +590,17 @@ config KEYBOARD_SUN4I_LRADC
> To compile this driver as a module, choose M here: the
> module will be called sun4i-lradc-keys.
>
> +config KEYBOARD_SUN4I_KEYPAD
> + tristate "Allwinner sun4i keypad support"
> + depends on ARCH_SUNXI
Is this IP found on all the know SoCs, or just a subset of them?
You probably want to add || COMPILE_TEST in that depends on too.
> + select INPUT_MATRIXKMAP
> + help
> + This selects support for the Allwinner keypad
> + on Allwinner sunxi SoCs.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called sun4i-keypad.
> +
> config KEYBOARD_DAVINCI
> tristate "TI DaVinci Key Scan"
> depends on ARCH_DAVINCI_DM365
> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> index 1d416dd..d9f54b4 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -57,6 +57,7 @@ obj-$(CONFIG_KEYBOARD_STMPE) += stmpe-keypad.o
> obj-$(CONFIG_KEYBOARD_STOWAWAY) += stowaway.o
> obj-$(CONFIG_KEYBOARD_ST_KEYSCAN) += st-keyscan.o
> obj-$(CONFIG_KEYBOARD_SUN4I_LRADC) += sun4i-lradc-keys.o
> +obj-$(CONFIG_KEYBOARD_SUN4I_KEYPAD) += sun4i-keypad.o
> obj-$(CONFIG_KEYBOARD_SUNKBD) += sunkbd.o
> obj-$(CONFIG_KEYBOARD_TC3589X) += tc3589x-keypad.o
> obj-$(CONFIG_KEYBOARD_TEGRA) += tegra-kbc.o
> diff --git a/drivers/input/keyboard/sun4i-keypad.c b/drivers/input/keyboard/sun4i-keypad.c
> new file mode 100644
> index 0000000..995f9665
> --- /dev/null
> +++ b/drivers/input/keyboard/sun4i-keypad.c
> @@ -0,0 +1,361 @@
> +/*
> + * Allwinner sun4i keypad Controller driver
> + *
> + * Copyright (C) 2015 Yassin Jaffer <yassinjaffer at gmail.com>
> + *
> + * Parts of this software are based on (derived from):
> + * Copyright (C) 2013-2015 liming at allwinnertech.com,
> + * qys<qinyongshen at allwinnertech.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/io.h>
> +#include <linux/interrupt.h>
> +#include <linux/err.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/of_platform.h>
> +#include <linux/slab.h>
> +#include <linux/input.h>
> +#include <linux/input/matrix_keypad.h>
> +
> +/*
> + * Keypad Controller registers
> + */
> +#define KP_CTL 0x00 /* Keypad Control register */
> +#define KP_TIMING 0x04 /* Keypad Timing register */
> +#define KP_INT_CFG 0x08 /* Keypad interrupt Config register */
> +#define KP_INT_STA 0x0c /* Keypad interrupt Status register */
> +
> +#define KP_IN_OFFSET 0x10 /* Keypad Input Data register 0 */
> +#define KP_INX_OFFSET(reg_n) (KP_IN_OFFSET + 4 * (reg_n))
> +
> +/* KP_CTL bits */
> +#define ENABLE(x) ((x) << 0)
> +#define COLMASK(x) ((~x & 0xff) << 8)
> +#define ROWMASK(x) ((~x & 0xff) << 16)
Having the name of the register in that define would be great, to spot
more easily issues (writing a value to another register, for example).
Something like KP_CTL_ENABLE(x) in this case.
> +/* KP_TIMING bits */
> +#define SCAN_CYCLE(x) ((x) << 0)
> +#define DBC_CYCLE(x) ((x) << 16)
> +
> +/* KP_INT_CFG bits */
> +#define KP_IRQ_FEDGE BIT(0)
> +#define KP_IRQ_REDGE BIT(1)
> +
> +/* KP_INT_STA bits */
> +#define KP_STA_FEDGE BIT(0)
> +#define KP_STA_REDGE BIT(1)
> +
> +#define KP_MAX_ROWS 8
> +#define KP_MAX_COLS 8
> +#define N_ROWS_REG 2
> +#define KP_ROW_SHIFT 3
> +#define KP_BIT_SHIFT 32
> +
> +#define MAX_MATRIX_KEY_NUM (KP_MAX_ROWS * KP_MAX_COLS)
> +
> +#define KP_BASE_CLK 1000000
> +#define MIN_CYCLE 0x10
> +#define MIN_SCAN_CYCLE 0x100
> +#define MIN_DBC_CYCLE 0x200
> +
> +/*
> + * keypad Controller structure: stores sunxi keypad controller information
> + *
> + * @dev: parent device
> + * @input: pointer to input device object
> + * @apb_clk: keypad Controller APB clock
> + * @clk: keypad Controller mod clock
> + * @base: keypad controller registers
> + * @irq: interrupt
> + * @rows_en_mask: Masks for enabled rows
> + * @cols_en_mask: Masks for enabled cols
> + * @keymap: matrix scan code table for keycodes
> + * @key_press_state: cached keys press state
> + * @debounce_cycl: keypad specific debounce cycle
> + * @scan_cycl: keypad specific scan cycle
> + * @autorepeat: flag for auto repetition
> + */
> +struct sun4i_keypad_data {
> + struct device *dev;
> + struct input_dev *input;
> +
> + struct clk *apb_clk;
> + struct clk *clk;
> + void __iomem *base;
> + int irq;
> +
> + unsigned short rows_en_mask;
> + unsigned short cols_en_mask;
> +
> + unsigned short keymap[MAX_MATRIX_KEY_NUM];
> +
> + unsigned int press_state[N_ROWS_REG];
> +
> + unsigned int debounce_cycl;
> + unsigned int scan_cycl;
> + bool autorepeat;
> +};
> +
> +static void sun4i_keypad_scan(struct sun4i_keypad_data *keypad, bool edge)
> +{
> + struct input_dev *input_dev = keypad->input;
> + u32 key_scan[N_ROWS_REG];
> + unsigned long change;
> + unsigned short code;
> + int reg_nr, bit_nr, key_up;
> +
> + for (reg_nr = 0; reg_nr < N_ROWS_REG; reg_nr++) {
> + key_scan[reg_nr] = ~(readl(keypad->base +
> + KP_INX_OFFSET(reg_nr)));
> +
> + change = edge ? key_scan[reg_nr] :
> + keypad->press_state[reg_nr] ^ key_scan[reg_nr];
> +
> + key_up = edge || (change & keypad->press_state[reg_nr]);
> +
> + for_each_set_bit(bit_nr, &change, BITS_PER_LONG) {
> + code = keypad->keymap[KP_BIT_SHIFT * reg_nr + bit_nr];
> + input_report_key(input_dev, code, key_up);
> + input_sync(input_dev);
I don't think you need to do an input_sync call each time for eah
input_report_key.
> + }
> +
> + keypad->press_state[reg_nr] = edge ? 0 : key_scan[reg_nr];
> + }
> +}
> +
> +static irqreturn_t sun4i_keypad_irq(int irq, void *dev_id)
> +{
> + struct sun4i_keypad_data *keypad = dev_id;
> + u32 intr_status;
> +
> + intr_status = readl(keypad->base + KP_INT_STA);
> +
> + /* release only gives a valid information for a single key release */
> + if (intr_status & KP_STA_REDGE)
> + sun4i_keypad_scan(keypad, true);
> +
> + /* press does not give valid information when
> + * multiple rows are selected
> + */
/*
* This is the multi-line comment style
*/
> + if (intr_status & KP_STA_FEDGE)
> + sun4i_keypad_scan(keypad, false);
> +
> + writel(intr_status, keypad->base + KP_INT_STA);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int sun4i_keypad_open(struct input_dev *dev)
> +{
> + struct sun4i_keypad_data *keypad = input_get_drvdata(dev);
> + int reg_nr;
> +
> + if (clk_prepare_enable(keypad->apb_clk))
> + return -EINVAL;
> +
> + if (clk_prepare_enable(keypad->clk)) {
> + clk_disable_unprepare(keypad->apb_clk);
> + return -EINVAL;
> + }
> +
> + for (reg_nr = 0; reg_nr < N_ROWS_REG; reg_nr++)
> + keypad->press_state[reg_nr] = ~(readl(keypad->base +
> + KP_INX_OFFSET(reg_nr)));
> +
> + writel(KP_IRQ_FEDGE | KP_IRQ_REDGE, keypad->base + KP_INT_CFG);
> +
> + writel(SCAN_CYCLE(keypad->scan_cycl) |
> + DBC_CYCLE(keypad->debounce_cycl), keypad->base + KP_TIMING);
> +
> + writel(ENABLE(1) | ROWMASK(keypad->rows_en_mask) |
> + COLMASK(keypad->cols_en_mask), keypad->base + KP_CTL);
> +
> + return 0;
> +}
> +
> +static void sun4i_keypad_close(struct input_dev *dev)
> +{
> + struct sun4i_keypad_data *keypad = input_get_drvdata(dev);
> +
> + writel(ENABLE(0) | ROWMASK(keypad->rows_en_mask) |
> + COLMASK(keypad->cols_en_mask), keypad->base + KP_CTL);
> +
> + clk_disable_unprepare(keypad->clk);
> + clk_disable_unprepare(keypad->apb_clk);
> +}
> +
> +static int sun4i_keypad_parse_dt(struct device *dev,
> + struct sun4i_keypad_data *keypad)
> +{
> + struct device_node *np;
> +
> + np = dev->of_node;
> + if (!np)
> + return -EINVAL;
> +
> + of_property_read_u32(np, "debounce-cycle", &keypad->debounce_cycl);
> + if (keypad->debounce_cycl < MIN_CYCLE)
> + keypad->debounce_cycl = MIN_DBC_CYCLE;
> +
> + of_property_read_u32(np, "scan-cycle", &keypad->scan_cycl);
> + if (keypad->scan_cycl < MIN_CYCLE)
> + keypad->scan_cycl = MIN_SCAN_CYCLE;
> +
> + if (of_property_read_bool(np, "autorepeat"))
> + keypad->autorepeat = true;
> +
> + return 0;
> +}
> +
> +static int sun4i_keypad_probe(struct platform_device *pdev)
> +{
> + struct sun4i_keypad_data *keypad;
> + struct device *dev = &pdev->dev;
> + int row, col, code;
> + int ret = 0;
> +
> + keypad = devm_kzalloc(dev, sizeof(struct sun4i_keypad_data),
> + GFP_KERNEL);
> + if (!keypad)
> + return -ENOMEM;
> +
> + ret = sun4i_keypad_parse_dt(dev, keypad);
> + if (ret)
> + return ret;
> +
> + keypad->base = devm_ioremap_resource(dev,
> + platform_get_resource(pdev, IORESOURCE_MEM, 0));
Usually, it gets called on two lines to make it clearer.
> + if (IS_ERR(keypad->base))
> + return PTR_ERR(keypad->base);
> +
> + keypad->dev = dev;
> + keypad->input = devm_input_allocate_device(dev);
> + if (!keypad->input)
> + return -ENOMEM;
> +
> + keypad->input->name = pdev->name;
> + keypad->input->phys = "sun4i_keypad/input0";
> +
> + keypad->input->id.bustype = BUS_HOST;
> + keypad->input->id.vendor = 0x0001;
> + keypad->input->id.product = 0x0001;
> + keypad->input->id.version = 0x0100;
> +
> + keypad->input->open = sun4i_keypad_open;
> + keypad->input->close = sun4i_keypad_close;
> +
> + /* matrix keypad keymap as:
> + * row << 24 | column << 16 | key-code
> + */
> + ret = matrix_keypad_build_keymap(NULL, NULL,
> + KP_MAX_ROWS,
> + KP_MAX_COLS,
> + keypad->keymap,
> + keypad->input);
> + if (ret) {
> + dev_err(dev, "failed to build keymap\n");
> + return ret;
> + }
> +
> + /* Search for enabled rows and cols */
> + for (row = 0; row < KP_MAX_ROWS; row++) {
> + for (col = 0; col < KP_MAX_COLS; col++) {
> + code = MATRIX_SCAN_CODE(row, col, KP_ROW_SHIFT);
> + if (keypad->keymap[code] != KEY_RESERVED) {
> + keypad->rows_en_mask |= 1 << row;
> + keypad->cols_en_mask |= 1 << col;
> + }
> + }
> + }
> +
> + if (keypad->autorepeat)
> + __set_bit(EV_REP, keypad->input->evbit);
> +
> + input_set_capability(keypad->input, EV_MSC, MSC_SCAN);
> + input_set_drvdata(keypad->input, keypad);
> +
> + keypad->irq = platform_get_irq(pdev, 0);
> + if (keypad->irq < 0) {
> + dev_err(dev, "failed to get keypad IRQ\n");
> + return -ENXIO;
> + }
> +
> + ret = devm_request_irq(dev, keypad->irq,
> + sun4i_keypad_irq, 0,
> + "sun4i-a10-keypad", keypad);
> + if (ret) {
> + dev_err(dev, "failed to request IRQ\n");
> + return ret;
> + }
> +
> + keypad->apb_clk = devm_clk_get(dev, "apb");
> + if (IS_ERR(keypad->apb_clk)) {
> + dev_err(dev, "failed to get a apb clock.\n");
> + return PTR_ERR(keypad->apb_clk);
> + }
> +
> + keypad->clk = devm_clk_get(dev, "keypad");
> + if (IS_ERR(keypad->clk)) {
> + dev_err(dev, "failed to get a keypad clock.\n");
> + return PTR_ERR(keypad->clk);
> + }
> +
> + ret = clk_set_rate(keypad->clk, KP_BASE_CLK);
> + if (ret) {
> + dev_err(dev, "set keypad base clock failed!\n");
> + return ret;
> + }
Do you need that rate to be enforced, or is it some leftover from the
allwinner BSP?
> + ret = input_register_device(keypad->input);
> + if (ret)
> + return ret;
> +
> + platform_set_drvdata(pdev, keypad);
> +
> + return 0;
> +}
> +
> +static int sun4i_keypad_remove(struct platform_device *pdev)
> +{
> + struct sun4i_keypad_data *keypad = platform_get_drvdata(pdev);
> +
> + free_irq(keypad->irq, keypad);
> + input_unregister_device(keypad->input);
> + kfree(keypad);
The point of using devm_ functions is precisely to remove the removal
code from both the probe error path (and you did so there), and from
the remove.
> +
> + return 0;
> +}
> +
> +static const struct of_device_id sun4i_keypad_of_match[] = {
> + { .compatible = "allwinner,sun4i-a10-keypad", },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, sun4i_keypad_of_match);
> +
> +static struct platform_driver sun4i_keypad_driver = {
> + .driver = {
> + .name = "sun4i-a10-keypad",
> + .of_match_table = of_match_ptr(sun4i_keypad_of_match),
> + },
> + .probe = sun4i_keypad_probe,
> + .remove = sun4i_keypad_remove,
> +};
> +
> +module_platform_driver(sun4i_keypad_driver);
> +
> +MODULE_DESCRIPTION("Allwinner sun4i keypad controller driver");
> +MODULE_AUTHOR("Yassin Jaffer <yassinjaffer at gmail.com>");
> +MODULE_LICENSE("GPL");
> +
It looks good otherwise, thanks!
Maxime
--
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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