[PATCH 3/4] input: Add new sun4i-keypad driver
yassinjaffer at gmail.com
yassinjaffer at gmail.com
Tue Sep 15 07:05:56 PDT 2015
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
+ 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)
+
+/* 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);
+ }
+
+ 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
+ */
+ 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));
+ 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;
+ }
+
+ 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);
+
+ 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");
+
--
1.9.1
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