[PATCH RESEND v3 1/2] input: keyboard: Add keys driver for the LPC32xx SoC
Roland Stigge
stigge at antcom.de
Sat May 5 08:00:20 EDT 2012
This patch adds a driver for the key scan interface of the LPC32xx SoC
Signed-off-by: Roland Stigge <stigge at antcom.de>
---
Applies to v3.4-rc5
Please pick this patch for the input subsystem.
Changes since v2:
* Fixed case of lpc32XX_* -> lpc32xx_*
* Removed unnecessary casts
* Removed unnecessary unlikely()
* Use unsigned for key bits
* Included Russell's lpc32xx_mod_states() algorithm change suggestion
* Replaced (res == NULL) with (!res)
* clk_enable() -> clk_prepare_enable()
* Moved clk_prepare_enable() and clk_disable_unprepare() to input's
open()/close() callbacks to save power
* Handle clk_prepare_enable() return value appropriately
* DT: Use "keypad,num-rows", "keypad,num-columns" and "linux,keymap" properties
Thanks to Axel Lin and Russell King for reviewing!
Documentation/devicetree/bindings/input/lpc32xx-key.txt | 28 +
drivers/input/keyboard/Kconfig | 10
drivers/input/keyboard/Makefile | 1
drivers/input/keyboard/lpc32xx-keys.c | 382 ++++++++++++++++
4 files changed, 421 insertions(+)
--- /dev/null
+++ linux-2.6/Documentation/devicetree/bindings/input/lpc32xx-key.txt
@@ -0,0 +1,28 @@
+NXP LPC32xx Key Scan Interface
+
+Required Properties:
+- compatible: Should be "nxp,lpc3220-key"
+- reg: Physical base address of the controller and length of memory mapped
+ region.
+- interrupts: The interrupt number to the cpu.
+- keypad,num-rows: Number of rows and columns, e.g. 1: 1x1, 6: 6x6
+- keypad,num-columns: Must be equal to keypad,num-rows since LPC32xx only
+ supports square matrices
+- nxp,debounce-delay-ms: Debounce delay in ms
+- nxp,scan-delay-ms: Repeated scan period in ms
+- linux,keymap: the key-code to be reported when the key is pressed
+ and released, see also
+ Documentation/devicetree/bindings/input/matrix-keymap.txt
+
+Example:
+
+ key at 40050000 {
+ compatible = "nxp,lpc3220-key";
+ reg = <0x40050000 0x1000>;
+ interrupts = <54 0>;
+ keypad,num-rows = <1>;
+ keypad,num-columns = <1>;
+ nxp,debounce-delay-ms = <3>;
+ nxp,scan-delay-ms = <34>;
+ linux,keymap = <0x00000002>;
+ };
--- linux-2.6.orig/drivers/input/keyboard/Kconfig
+++ linux-2.6/drivers/input/keyboard/Kconfig
@@ -318,6 +318,16 @@ config KEYBOARD_LOCOMO
To compile this driver as a module, choose M here: the
module will be called locomokbd.
+config KEYBOARD_LPC32XX
+ tristate "LPC32XX matrix key scanner support"
+ depends on ARCH_LPC32XX
+ help
+ Say Y here if you want to use NXP LPC32XX SoC key scanner interface,
+ connected to a key matrix.
+
+ To compile this driver as a module, choose M here: the
+ module will be called lpc32xx-keys.
+
config KEYBOARD_MAPLE
tristate "Maple bus keyboard"
depends on SH_DREAMCAST && MAPLE
--- linux-2.6.orig/drivers/input/keyboard/Makefile
+++ linux-2.6/drivers/input/keyboard/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_KEYBOARD_HP7XX) += jornada
obj-$(CONFIG_KEYBOARD_LKKBD) += lkkbd.o
obj-$(CONFIG_KEYBOARD_LM8323) += lm8323.o
obj-$(CONFIG_KEYBOARD_LOCOMO) += locomokbd.o
+obj-$(CONFIG_KEYBOARD_LPC32XX) += lpc32xx-keys.o
obj-$(CONFIG_KEYBOARD_MAPLE) += maple_keyb.o
obj-$(CONFIG_KEYBOARD_MATRIX) += matrix_keypad.o
obj-$(CONFIG_KEYBOARD_MAX7359) += max7359_keypad.o
--- /dev/null
+++ linux-2.6/drivers/input/keyboard/lpc32xx-keys.c
@@ -0,0 +1,382 @@
+/*
+ * NXP LPC32xx SoC Key Scan Interface
+ *
+ * Authors:
+ * Kevin Wells <kevin.wells at nxp.com>
+ * Roland Stigge <stigge at antcom.de>
+ *
+ * Copyright (C) 2010 NXP Semiconductors
+ * Copyright (C) 2012 Roland Stigge
+ *
+ * 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/module.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/irq.h>
+#include <linux/pm.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+/*
+ * Key scanner register offsets
+ */
+#define LPC32XX_KS_DEB(x) ((x) + 0x00)
+#define LPC32XX_KS_STATE_COND(x) ((x) + 0x04)
+#define LPC32XX_KS_IRQ(x) ((x) + 0x08)
+#define LPC32XX_KS_SCAN_CTL(x) ((x) + 0x0C)
+#define LPC32XX_KS_FAST_TST(x) ((x) + 0x10)
+#define LPC32XX_KS_MATRIX_DIM(x) ((x) + 0x14)
+#define LPC32XX_KS_DATA(x, y) ((x) + 0x40 + ((y) << 2))
+
+#define LPC32XX_KSCAN_DEB_NUM_DEB_PASS(n) ((n) & 0xFF)
+
+#define LPC32XX_KSCAN_SCOND_IN_IDLE 0x0
+#define LPC32XX_KSCAN_SCOND_IN_SCANONCE 0x1
+#define LPC32XX_KSCAN_SCOND_IN_IRQGEN 0x2
+#define LPC32XX_KSCAN_SCOND_IN_SCAN_MATRIX 0x3
+
+#define LPC32XX_KSCAN_IRQ_PENDING_CLR 0x1
+
+#define LPC32XX_KSCAN_SCTRL_SCAN_DELAY(n) ((n) & 0xFF)
+
+#define LPC32XX_KSCAN_FTST_FORCESCANONCE 0x1
+#define LPC32XX_KSCAN_FTST_USE32K_CLK 0x2
+
+#define LPC32XX_KSCAN_MSEL_SELECT(n) ((n) & 0xF)
+
+/*
+ * Key scanner platform configuration structure
+ */
+struct lpc32xx_kscan_cfg {
+ u32 matrix_sz; /* Size of matrix in XxY, ie. 3 = 3x3 */
+ int *keymap; /* Pointer to key map for the scan matrix */
+ u32 deb_clks; /* Debounce clocks (based on 32KHz clock) */
+ u32 scan_delay; /* Scan delay (based on 32KHz clock) */
+};
+
+struct lpc32xx_kscan_drv {
+ struct input_dev *input;
+ struct lpc32xx_kscan_cfg *kscancfg;
+ struct clk *clk;
+ void __iomem *kscan_base;
+ int irq;
+ u8 lastkeystates[8];
+};
+
+static void lpc32xx_mod_states(struct lpc32xx_kscan_drv *kscandat, int off)
+{
+ u8 key;
+ int j;
+ unsigned changed, scancode, keycode;
+
+ key = readl(LPC32XX_KS_DATA(kscandat->kscan_base, off));
+ changed = key ^ kscandat->lastkeystates[off];
+ if (changed) {
+ for (j = 0; j < kscandat->kscancfg->matrix_sz; j++) {
+ if (changed & (1 << j)) {
+ /* Key state changed, signal an event */
+ scancode =
+ (j * kscandat->kscancfg->matrix_sz) + off;
+ keycode = kscandat->kscancfg->keymap[scancode];
+ input_report_key(kscandat->input, keycode,
+ key & (1 << j));
+ }
+ }
+
+ kscandat->lastkeystates[off] = key;
+ }
+}
+
+static irqreturn_t lpc32xx_kscan_irq(int irq, void *dev_id)
+{
+ int i;
+ struct lpc32xx_kscan_drv *kscandat = dev_id;
+
+ for (i = 0; i < kscandat->kscancfg->matrix_sz; i++)
+ lpc32xx_mod_states(kscandat, i);
+
+ writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
+
+ input_sync(kscandat->input);
+
+ return IRQ_HANDLED;
+}
+
+static int lpc32xx_kscan_open(struct input_dev *dev)
+{
+ struct lpc32xx_kscan_drv *kscandat = input_get_drvdata(dev);
+
+ return clk_prepare_enable(kscandat->clk);
+}
+
+static void lpc32xx_kscan_close(struct input_dev *dev)
+{
+ struct lpc32xx_kscan_drv *kscandat = input_get_drvdata(dev);
+
+ clk_disable_unprepare(kscandat->clk);
+}
+
+#ifdef CONFIG_OF
+static struct lpc32xx_kscan_cfg *lpc32xx_parse_dt(struct device *dev)
+{
+ struct lpc32xx_kscan_cfg *pdata;
+ struct device_node *np = dev->of_node;
+ int key_count;
+ int i;
+ u32 rows, columns;
+ const __be32 *prop;
+ int proplen;
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata) {
+ dev_err(dev, "could not allocate memory for platform data\n");
+ return NULL;
+ }
+
+ of_property_read_u32(np, "keypad,num-rows", &rows);
+ of_property_read_u32(np, "keypad,num-columns", &columns);
+ if (!rows || rows != columns) {
+ dev_err(dev, "rows and columns must be specified and be equal!\n");
+ return NULL;
+ }
+
+ pdata->matrix_sz = rows;
+ key_count = rows * columns;
+
+ of_property_read_u32(np, "nxp,debounce-delay-ms", &pdata->deb_clks);
+ of_property_read_u32(np, "nxp,scan-delay-ms", &pdata->scan_delay);
+ if (!pdata->deb_clks || !pdata->scan_delay) {
+ dev_err(dev, "debounce or scan delay not specified\n");
+ return NULL;
+ }
+
+ pdata->keymap = devm_kzalloc(dev, sizeof(int) * key_count, GFP_KERNEL);
+ if (!pdata->keymap) {
+ dev_err(dev, "could not allocate memory for keymap\n");
+ return NULL;
+ }
+
+ prop = of_get_property(np, "linux,keymap", &proplen);
+ if (!prop) {
+ dev_err(dev, "linux,keymap not specified\n");
+ return NULL;
+ }
+
+ if (proplen % sizeof(u32)) {
+ dev_err(dev, "bad linux,keymap property size: %d\n", proplen);
+ return NULL;
+ }
+ proplen /= sizeof(u32);
+
+ for (i = 0; i < proplen; i++) {
+ u32 tmp = be32_to_cpup(prop + i);
+ u32 row, column, key_code;
+
+ row = (tmp >> 24) & 0xff;
+ column = (tmp >> 16) & 0xff;
+ key_code = tmp & 0xffff;
+ pdata->keymap[row * columns + column] = key_code;
+ }
+
+ return pdata;
+}
+#else
+static struct lpc32xx_kscan_cfg *lpc32xx_parse_dt(struct device *dev)
+{
+ return NULL;
+}
+#endif
+
+static int __devinit lpc32xx_kscan_probe(struct platform_device *pdev)
+{
+ struct lpc32xx_kscan_drv *kscandat;
+ struct resource *res;
+ int retval, i, keynum;
+
+ kscandat = kzalloc(sizeof(struct lpc32xx_kscan_drv), GFP_KERNEL);
+ if (!kscandat) {
+ dev_err(&pdev->dev, "failed to allocate memory\n");
+ return -ENOMEM;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "failed to get platform I/O memory\n");
+ retval = -EBUSY;
+ goto out1;
+ }
+
+ kscandat->kscan_base = devm_request_and_ioremap(&pdev->dev, res);
+ if (kscandat->kscan_base == NULL) {
+ dev_err(&pdev->dev, "failed to request and remap I/O memory\n");
+ retval = -EBUSY;
+ goto out1;
+ }
+
+ /* Get the key scanner clock */
+ kscandat->clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(kscandat->clk)) {
+ dev_err(&pdev->dev, "failed to get clock\n");
+ retval = -ENODEV;
+ goto out1;
+ }
+
+ kscandat->irq = platform_get_irq(pdev, 0);
+ if ((kscandat->irq < 0) || (kscandat->irq >= NR_IRQS)) {
+ dev_err(&pdev->dev, "failed to get platform irq\n");
+ retval = -EINVAL;
+ goto out2;
+ }
+ retval = request_irq(kscandat->irq, lpc32xx_kscan_irq,
+ 0, pdev->name, kscandat);
+ if (retval) {
+ dev_err(&pdev->dev, "failed to request irq\n");
+ goto out2;
+ }
+
+ kscandat->input = input_allocate_device();
+ if (kscandat->input == NULL) {
+ dev_err(&pdev->dev, "failed to allocate device\n");
+ retval = -ENOMEM;
+ goto out3;
+ }
+
+ if (pdev->dev.of_node)
+ kscandat->kscancfg = lpc32xx_parse_dt(&pdev->dev);
+ else
+ kscandat->kscancfg = pdev->dev.platform_data;
+ if (!kscandat->kscancfg) {
+ dev_err(&pdev->dev, "failed to get platform data\n");
+ retval = -EINVAL;
+ goto out4;
+ }
+
+ platform_set_drvdata(pdev, kscandat);
+
+ /* Setup key input */
+ kscandat->input->evbit[0] = BIT_MASK(EV_KEY);
+ kscandat->input->name = pdev->name;
+ kscandat->input->phys = "matrix-keys/input0";
+ kscandat->input->dev.parent = &pdev->dev;
+ kscandat->input->id.vendor = 0x0001;
+ kscandat->input->id.product = 0x0001;
+ kscandat->input->id.version = 0x0100;
+ kscandat->input->open = &lpc32xx_kscan_open;
+ kscandat->input->close = &lpc32xx_kscan_close;
+ keynum = kscandat->kscancfg->matrix_sz * kscandat->kscancfg->matrix_sz;
+ for (i = 0; i < keynum; i++)
+ __set_bit(kscandat->kscancfg->keymap[i],
+ kscandat->input->keybit);
+
+ input_set_drvdata(kscandat->input, kscandat);
+ input_set_capability(kscandat->input, EV_MSC, MSC_SCAN);
+
+ retval = input_register_device(kscandat->input);
+ if (retval) {
+ dev_err(&pdev->dev, "failed to register input device\n");
+ goto out4;
+ }
+
+ /* Configure the key scanner */
+ writel(kscandat->kscancfg->deb_clks,
+ LPC32XX_KS_DEB(kscandat->kscan_base));
+ writel(kscandat->kscancfg->scan_delay,
+ LPC32XX_KS_SCAN_CTL(kscandat->kscan_base));
+ writel(LPC32XX_KSCAN_FTST_USE32K_CLK,
+ LPC32XX_KS_FAST_TST(kscandat->kscan_base));
+ writel(kscandat->kscancfg->matrix_sz,
+ LPC32XX_KS_MATRIX_DIM(kscandat->kscan_base));
+ writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
+
+ return 0;
+
+out4:
+ input_free_device(kscandat->input);
+out3:
+ free_irq(kscandat->irq, pdev);
+out2:
+ clk_put(kscandat->clk);
+out1:
+ kfree(kscandat);
+
+ return retval;
+}
+
+static int __devexit lpc32xx_kscan_remove(struct platform_device *pdev)
+{
+ struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev);
+
+ free_irq(kscandat->irq, pdev);
+ input_unregister_device(kscandat->input);
+ clk_put(kscandat->clk);
+ kfree(kscandat);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int lpc32xx_kscan_suspend(struct platform_device *pdev,
+ pm_message_t state)
+{
+ struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev);
+
+ /* Clear IRQ and disable clock */
+ writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
+ clk_disable_unprepare(kscandat->clk);
+
+ return 0;
+}
+
+static int lpc32xx_kscan_resume(struct platform_device *pdev)
+{
+ struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev);
+
+ /* Enable clock and clear IRQ */
+ clk_prepare_enable(kscandat->clk);
+ writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
+
+ return 0;
+}
+#else
+#define lpc32xx_kscan_suspend NULL
+#define lpc32xx_kscan_resume NULL
+#endif
+
+#ifdef CONFIG_OF
+static const struct of_device_id lpc32xx_kscan_match[] = {
+ { .compatible = "nxp,lpc3220-key" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, lpc32xx_kscan_match);
+#endif
+
+static struct platform_driver lpc32xx_kscan_driver = {
+ .probe = lpc32xx_kscan_probe,
+ .remove = __devexit_p(lpc32xx_kscan_remove),
+ .suspend = lpc32xx_kscan_suspend,
+ .resume = lpc32xx_kscan_resume,
+ .driver = {
+ .name = "lpc32xx_keys",
+ .of_match_table = of_match_ptr(lpc32xx_kscan_match),
+ }
+};
+
+module_platform_driver(lpc32xx_kscan_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Kevin Wells <kevin.wells at nxp.com>");
+MODULE_AUTHOR("Roland Stigge <stigge at antcom.de>");
+MODULE_DESCRIPTION("Key scanner driver for LPC32XX devices");
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