[RFC PATCHv3 5/6] input: Add TI-Nspire keypad driver
Daniel Tang
dt.tangr at gmail.com
Sun May 12 00:23:00 EDT 2013
Signed-off-by: Daniel Tang <dt.tangr at gmail.com>
---
drivers/input/keyboard/Kconfig | 10 ++
drivers/input/keyboard/Makefile | 1 +
drivers/input/keyboard/nspire-keypad.c | 315 +++++++++++++++++++++++++++++++++
3 files changed, 326 insertions(+)
create mode 100644 drivers/input/keyboard/nspire-keypad.c
diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index 62a2c0e..bdbda87 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -418,6 +418,16 @@ config KEYBOARD_NOMADIK
To compile this driver as a module, choose M here: the
module will be called nmk-ske-keypad.
+config KEYBOARD_NSPIRE
+ tristate "TI-NSPIRE builtin keyboard"
+ depends on ARCH_NSPIRE
+ select INPUT_MATRIXKMAP
+ help
+ Say Y here if you want to use the builtin keypad on the TI-NSPIRE.
+
+ To compile this driver as a module, choose M here: the
+ module will be called nspire-keypad.
+
config KEYBOARD_TEGRA
tristate "NVIDIA Tegra internal matrix keyboard controller support"
depends on ARCH_TEGRA && OF
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 0c43e8c..a699b61 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_KEYBOARD_MCS) += mcs_touchkey.o
obj-$(CONFIG_KEYBOARD_MPR121) += mpr121_touchkey.o
obj-$(CONFIG_KEYBOARD_NEWTON) += newtonkbd.o
obj-$(CONFIG_KEYBOARD_NOMADIK) += nomadik-ske-keypad.o
+obj-$(CONFIG_KEYBOARD_NSPIRE) += nspire-keypad.o
obj-$(CONFIG_KEYBOARD_OMAP) += omap-keypad.o
obj-$(CONFIG_KEYBOARD_OMAP4) += omap4-keypad.o
obj-$(CONFIG_KEYBOARD_OPENCORES) += opencores-kbd.o
diff --git a/drivers/input/keyboard/nspire-keypad.c b/drivers/input/keyboard/nspire-keypad.c
new file mode 100644
index 0000000..e863f14
--- /dev/null
+++ b/drivers/input/keyboard/nspire-keypad.c
@@ -0,0 +1,315 @@
+/*
+ * linux/drivers/input/keyboard/nspire-keypad.c
+ *
+ * Copyright (C) 2013 Daniel Tang <tangrs at tangrs.id.au>
+ *
+ * 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/input/matrix_keypad.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/of.h>
+
+#define KEYPAD_SCAN_MODE 0x00
+#define KEYPAD_CNTL 0x04
+#define KEYPAD_INT 0x08
+#define KEYPAD_INTMSK 0x0C
+
+#define KEYPAD_DATA 0x10
+#define KEYPAD_GPIO 0x30
+
+#define KEYPAD_UNKNOWN_INT 0x40
+#define KEYPAD_UNKNOWN_INT_STS 0x44
+
+#define KEYPAD_BITMASK_COLS 11
+#define KEYPAD_BITMASK_ROWS 8
+
+struct nspire_keypad {
+ spinlock_t lock;
+
+ void __iomem *reg_base;
+ int irq;
+ u32 int_mask;
+
+ struct input_dev *input;
+ struct clk *clk;
+
+ struct matrix_keymap_data *keymap;
+ int row_shift;
+
+ /* Maximum delay estimated assuming 33MHz APB */
+ u32 scan_interval; /* In microseconds (~2000us max) */
+ u32 row_delay; /* In microseconds (~500us max) */
+
+ bool active_low;
+};
+
+static inline void nspire_report_state(struct nspire_keypad *keypad,
+ int row, int col, unsigned int state)
+{
+ int code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
+ unsigned short *keymap = keypad->input->keycode;
+
+ state = keypad->active_low ? !state : !!state;
+ input_report_key(keypad->input, keymap[code], state);
+}
+
+static irqreturn_t nspire_keypad_irq(int irq, void *dev_id)
+{
+ struct nspire_keypad *keypad = dev_id;
+ u32 int_sts;
+ u16 state[8];
+ int row, col;
+
+ int_sts = readl(keypad->reg_base + KEYPAD_INT) & keypad->int_mask;
+
+ if (!int_sts)
+ return IRQ_NONE;
+
+ spin_lock(&keypad->lock);
+
+ memcpy_fromio(state, keypad->reg_base + KEYPAD_DATA, sizeof(state));
+
+ for (row = 0; row < KEYPAD_BITMASK_ROWS; row++) {
+ u16 bits = state[row];
+ for (col = 0; col < KEYPAD_BITMASK_COLS; col++)
+ nspire_report_state(keypad, row, col, bits & (1<<col));
+ }
+ input_sync(keypad->input);
+ writel(0x3, keypad->reg_base + KEYPAD_INT);
+
+ spin_unlock(&keypad->lock);
+
+ return IRQ_HANDLED;
+}
+
+static int nspire_keypad_chip_init(struct nspire_keypad *keypad)
+{
+ unsigned long val = 0, cycles_per_us, delay_cycles, row_delay_cycles;
+
+ cycles_per_us = (clk_get_rate(keypad->clk) / 1000000);
+ if (cycles_per_us == 0)
+ cycles_per_us = 1;
+
+ delay_cycles = cycles_per_us * keypad->scan_interval;
+ WARN_ON(delay_cycles >= (1<<16)); /* Overflow */
+ delay_cycles &= 0xffff;
+
+ row_delay_cycles = cycles_per_us * keypad->row_delay;
+ WARN_ON(row_delay_cycles >= (1<<14)); /* Overflow */
+ row_delay_cycles &= 0x3fff;
+
+
+ val |= (3<<0); /* Set scan mode to 3 (continuous scan) */
+ val |= (row_delay_cycles<<2); /* Delay between scanning each row */
+ val |= (delay_cycles<<16); /* Delay between scans */
+ writel(val, keypad->reg_base + KEYPAD_SCAN_MODE);
+
+ val = (KEYPAD_BITMASK_ROWS & 0xff) | (KEYPAD_BITMASK_COLS & 0xff)<<8;
+ writel(val, keypad->reg_base + KEYPAD_CNTL);
+
+ /* Enable interrupts */
+ keypad->int_mask = (1<<1);
+ writel(keypad->int_mask, keypad->reg_base + 0xc);
+
+ /* Disable GPIO interrupts to prevent hanging on touchpad */
+ /* Possibly used to detect touchpad events */
+ writel(0, keypad->reg_base + KEYPAD_UNKNOWN_INT);
+ /* Acknowledge existing interrupts */
+ writel(~0, keypad->reg_base + KEYPAD_UNKNOWN_INT_STS);
+
+ return 0;
+}
+
+static int nspire_keypad_probe(struct platform_device *pdev)
+{
+ const struct device_node *of_node = pdev->dev.of_node;
+ struct nspire_keypad *keypad;
+ struct input_dev *input;
+ struct resource *res;
+ struct clk *clk;
+ int irq, error;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "failed to get keypad irq\n");
+ return -EINVAL;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "missing platform resources\n");
+ return -EINVAL;
+ }
+
+ clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(clk)) {
+ dev_err(&pdev->dev, "unable to get clock\n");
+ return -EINVAL;
+ }
+
+ clk_prepare(clk);
+ error = clk_enable(clk);
+ if (error)
+ goto err_put_clk;
+
+ keypad = kzalloc(sizeof(struct nspire_keypad), GFP_KERNEL);
+ input = input_allocate_device();
+ if (!keypad || !input) {
+ dev_err(&pdev->dev, "failed to allocate keypad memory\n");
+ error = -ENOMEM;
+ goto err_free_mem;
+ }
+
+ error = of_property_read_u32(of_node, "scan-interval",
+ &keypad->scan_interval);
+ if (error) {
+ dev_err(&pdev->dev, "failed to get scan-interval\n");
+ goto err_free_mem;
+ }
+
+ error = of_property_read_u32(of_node, "row-delay",
+ &keypad->row_delay);
+ if (error) {
+ dev_err(&pdev->dev, "failed to get row-delay\n");
+ goto err_free_mem;
+ }
+
+ keypad->active_low = of_property_read_bool(of_node,
+ "active-low");
+
+ keypad->keymap = NULL;
+
+ keypad->row_shift = get_count_order(KEYPAD_BITMASK_COLS);
+ keypad->irq = irq;
+ keypad->clk = clk;
+ keypad->input = input;
+ spin_lock_init(&keypad->lock);
+
+ if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
+ dev_err(&pdev->dev, "failed to request I/O memory\n");
+ error = -EBUSY;
+ goto err_free_mem;
+ }
+
+ keypad->reg_base = ioremap(res->start, resource_size(res));
+ if (!keypad->reg_base) {
+ dev_err(&pdev->dev, "failed to remap I/O memory\n");
+ error = -ENXIO;
+ goto err_free_mem_region;
+ }
+
+ input->id.bustype = BUS_HOST;
+ input->name = "nspire-keypad";
+ input->dev.parent = &pdev->dev;
+
+ set_bit(EV_KEY, input->evbit);
+ set_bit(EV_REP, input->evbit);
+
+ error = matrix_keypad_build_keymap(keypad->keymap, "keymap",
+ KEYPAD_BITMASK_ROWS, KEYPAD_BITMASK_COLS, NULL, input);
+ if (error) {
+ dev_err(&pdev->dev, "building keymap failed\n");
+ goto err_iounmap;
+ }
+
+ error = nspire_keypad_chip_init(keypad);
+ if (error) {
+ dev_err(&pdev->dev, "unable to init keypad hardware\n");
+ goto err_iounmap;
+ }
+
+ error = request_irq(keypad->irq, nspire_keypad_irq, 0,
+ "nspire_keypad", keypad);
+ if (error) {
+ dev_err(&pdev->dev, "allocate irq %d failed\n", keypad->irq);
+ goto err_iounmap;
+ }
+
+ error = input_register_device(input);
+ if (error) {
+ dev_err(&pdev->dev,
+ "unable to register input device: %d\n", error);
+ goto err_free_irq;
+ }
+
+ platform_set_drvdata(pdev, keypad);
+
+ dev_info(&pdev->dev, "TI-NSPIRE keypad at %#08x ("
+ "scan_interval=%uus,row_delay=%uus"
+ "%s)\n", res->start,
+ keypad->row_delay,
+ keypad->scan_interval,
+ keypad->active_low ? ",active_low" : "");
+
+ return 0;
+
+err_free_irq:
+ free_irq(keypad->irq, keypad);
+err_iounmap:
+ iounmap(keypad->reg_base);
+err_free_mem_region:
+ release_mem_region(res->start, resource_size(res));
+err_free_mem:
+ input_free_device(input);
+ kfree(keypad);
+
+ clk_disable(clk);
+err_put_clk:
+ clk_unprepare(clk);
+ clk_put(clk);
+ return error;
+}
+
+static int nspire_keypad_remove(struct platform_device *pdev)
+{
+ struct nspire_keypad *keypad = platform_get_drvdata(pdev);
+ struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ free_irq(keypad->irq, keypad);
+
+ input_unregister_device(keypad->input);
+
+ iounmap(keypad->reg_base);
+ release_mem_region(res->start, resource_size(res));
+ kfree(keypad);
+
+ clk_disable(keypad->clk);
+ clk_unprepare(keypad->clk);
+ clk_put(keypad->clk);
+
+ return 0;
+}
+#ifdef CONFIG_OF
+static const struct of_device_id nspire_keypad_dt_match[] = {
+ { .compatible = "nspire-keypad" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, nspire_keypad_dt_match);
+#endif
+
+static struct platform_driver nspire_keypad_driver = {
+ .driver = {
+ .name = "nspire-keypad",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(nspire_keypad_dt_match),
+ },
+ .remove = nspire_keypad_remove,
+ .probe = nspire_keypad_probe,
+};
+
+module_platform_driver(nspire_keypad_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("TI-NSPIRE Keypad Driver");
--
1.8.1.3
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