[PATCHv2 2/4] Input: keypad: Add smsc ece1099 keypad driver

+ other external mailing list (did a reply to by mistake)

On Thu, Sep 6, 2012 at 11:04 AM, Poddar, Sourav [off-list ref] wrote:

Hi Vaibhav,

On Thu, Sep 6, 2012 at 12:01 AM, Vaibhav Hiremath [off-list ref] wrote:

quoted

On 9/5/2012 5:06 PM, Sourav Poddar wrote:

quoted

From: G, Manjunath Kondaiah <redacted>

SMSC ECE1099 is a keyboard scan or GPIO expansion device.The device
supports a keypad scan matrix of 23*8.This driver uses this
device as a keypad driver.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Benoit Cousson <redacted>
Cc: Felipe Balbi <redacted>
Cc: Santosh Shilimkar <redacted>
Signed-off-by: G, Manjunath Kondaiah <redacted>
Signed-off-by: Sourav Poddar <redacted>
Acked-by: Felipe Balbi <redacted>
---
Changes since v1:
 - Prevent the use of kfree since devm_kzalloc was used.
 - Use devexit around remove api
 drivers/input/keyboard/Kconfig               |   11 +
 drivers/input/keyboard/Makefile              |    1 +
 drivers/input/keyboard/smsc-ece1099-keypad.c |  306 ++++++++++++++++++++++++++
 3 files changed, 318 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/keyboard/smsc-ece1099-keypad.c

diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index c50fa75..2a2d374 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig

@@ -593,6 +593,17 @@ config KEYBOARD_TWL4030
        To compile this driver as a module, choose M here: the
        module will be called twl4030_keypad.

+config KEYBOARD_SMSC
+       tristate "SMSC ECE1099 keypad support"
+       depends on I2C=y

Any specific reason behind "=y"

Nope, my bad.."=y" should be dropped.

quoted

quoted

+       help
+         Say Y here if your board use the smsc keypad controller
+         for omap5 defconfig. It's safe to say enable this
+         even on boards that don't use the keypad controller.
+
+         To compile this driver as a module, choose M here: the
+         module will be called smsc-ece1099-keypad.
+
 config KEYBOARD_XTKBD
      tristate "XT keyboard"
      select SERIO

diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 44e7600..0f2aa26 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile

@@ -52,5 +52,6 @@ obj-$(CONFIG_KEYBOARD_TC3589X)              += tc3589x-keypad.o
 obj-$(CONFIG_KEYBOARD_TEGRA)         += tegra-kbc.o
 obj-$(CONFIG_KEYBOARD_TNETV107X)     += tnetv107x-keypad.o
 obj-$(CONFIG_KEYBOARD_TWL4030)               += twl4030_keypad.o
+obj-$(CONFIG_KEYBOARD_SMSC)            += smsc-ece1099-keypad.o
 obj-$(CONFIG_KEYBOARD_XTKBD)         += xtkbd.o
 obj-$(CONFIG_KEYBOARD_W90P910)               += w90p910_keypad.o

diff --git a/drivers/input/keyboard/smsc-ece1099-keypad.c b/drivers/input/keyboard/smsc-ece1099-keypad.c
new file mode 100644
index 0000000..71cd7d6
--- /dev/null
+++ b/drivers/input/keyboard/smsc-ece1099-keypad.c

@@ -0,0 +1,306 @@
+/*
+ * SMSC_ECE1099 Keypad driver
+ *
+ * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * 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/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/input/matrix_keypad.h>
+#include <linux/delay.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/smsc.h>
+#include <linux/of_gpio.h>
+#include <linux/of.h>
+
+#define KEYPRESS_TIME          200
+
+struct smsc_keypad {
+     struct smsc *smsc;
+     struct matrix_keymap_data *keymap_data;
+     unsigned int last_key_state[16];
+     unsigned int last_col;
+     unsigned int last_key_ms[16];
+     unsigned short *keymap;
+     struct i2c_client *client;
+     struct input_dev *input;
+     int rows, cols;
+     int row_shift;
+     bool no_autorepeat;
+     unsigned        irq;
+     struct device *dev;
+};
+
+static void smsc_kp_scan(struct smsc_keypad *kp)
+{
+     struct input_dev *input = kp->input;
+     int i, j;
+     int row, col;
+     int temp, code;
+     unsigned int new_state[16];
+     unsigned int bits_changed;
+     int this_ms;
+
+     smsc_write(kp->dev, SMSC_KP_INT_MASK, 0x00);
+     smsc_write(kp->dev, SMSC_KP_INT_STAT, 0xFF);
+
+     /* Scan for row and column */
+     for (i = 0; i < kp->cols; i++) {
+             smsc_write(kp->dev, SMSC_KP_OUT, SMSC_KSO_EVAL + i);
+             /* Read Row Status */
+             smsc_read(kp->dev, SMSC_KP_IN, &temp);
+             if (temp == 0xFF)
+                     continue;
+
+             col = i;
+             for (j = 0; j < kp->rows; j++) {
+                     if ((temp & 0x01) != 0x00) {
+                             temp = temp >> 1;
+                             continue;
+                     }
+
+                     row = j;
+                     new_state[col] =  (1 << row);
+                     bits_changed = kp->last_key_state[col] ^ new_state[col];
+                     this_ms = jiffies_to_msecs(jiffies);
+                     if (bits_changed != 0 || (!bits_changed &&
+                                     ((this_ms - kp->last_key_ms[col]) >= KEYPRESS_TIME))) {
+                             code = MATRIX_SCAN_CODE(row, col, kp->row_shift);
+                             input_event(input, EV_MSC, MSC_SCAN, code);
+                             input_report_key(input, kp->keymap[code], 1);
+                             input_report_key(input, kp->keymap[code], 0);
+                             kp->last_key_state[col] = new_state[col];
+                             if (kp->last_col != col)
+                                     kp->last_key_state[kp->last_col] = 0;
+                             kp->last_key_ms[col] = this_ms;
+                     }
+                     temp = temp >> 1;
+             }
+     }
+     input_sync(input);
+
+     smsc_write(kp->dev, SMSC_KP_INT_MASK, 0xFF);
+
+     /* Set up Low Power Mode (Wake-up) (0xFB) */
+     smsc_write(kp->dev, SMSC_WKUP_CTRL, SMSC_KP_SET_LOW_PWR);
+
+     /*Enable Keypad Scan (generate interrupt on key press) (0x40)*/
+     smsc_write(kp->dev, SMSC_KP_OUT, SMSC_KSO_ALL_LOW);
+}
+
+static irqreturn_t do_kp_irq(int irq, void *_kp)
+{
+     struct smsc_keypad *kp = _kp;
+     int int_status;
+
+     smsc_read(kp->dev, SMSC_KP_INT_STAT, &int_status);
+     if (int_status)
+             smsc_kp_scan(kp);
+
+     return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_OF
+static int __devinit smsc_keypad_parse_dt(struct device *dev,
+                             struct smsc_keypad *kp)
+{
+     struct device_node *np = dev->of_node;
+
+     if (!np) {
+             dev_err(dev, "missing DT data");
+             return -EINVAL;

Isn't you should return -ENXIO?

I think "EINVAL" is more apt as it will reflect that the user has not populated
the dt data and its an invalid argument.

quoted

quoted

+     }
+
+     of_property_read_u32(np, "keypad,num-rows", &kp->rows);
+     of_property_read_u32(np, "keypad,num-columns", &kp->cols);
+     if (!kp->rows || !kp->cols) {
+             dev_err(dev, "number of keypad rows/columns not specified\n");
+             return -EINVAL;
+     }
+
+     if (of_get_property(np, "linux,input-no-autorepeat", NULL))
+             kp->no_autorepeat = true;
+

You can use of_property_read_bool() here.

Ok.Will change.

quoted

quoted

+     return 0;
+}
+#else
+static inline int smsc_keypad_parse_dt(struct device *dev,
+                             struct smsc_keypad *kp)
+{
+     return -ENOSYS;
+}
+#endif
+
+static int __devinit
+smsc_probe(struct platform_device *pdev)
+{
+     struct device *dev = &pdev->dev;
+     struct smsc *smsc = dev_get_drvdata(pdev->dev.parent);
+     struct input_dev *input;
+     struct smsc_keypad *kp;
+     int ret = 0, error;
+     int col, i, max_keys, row_shift;
+     int irq;
+     int addr_start, addr;
+
+     kp = devm_kzalloc(dev, sizeof(*kp), GFP_KERNEL);
+
+     input = input_allocate_device();
+     if (!kp || !input) {
+             error = -ENOMEM;
+             goto err1;

You can directly return here.

Ok.

quoted

quoted

+     }
+
+     error = smsc_keypad_parse_dt(&pdev->dev, kp);
+     if (error)
+             return error;
+
+     /* Get the debug Device */
+     kp->input = input;
+     kp->smsc = smsc;
+     kp->irq = platform_get_irq(pdev, 0);
+     kp->dev = dev;
+
+     for (col = 0; col < 16; col++) {

Isn't this magic no 16 should come from DT??

Yes, actually its the number of columns which is coming from
dt only. I will replace it with the correct variable containg this data.

quoted

quoted

+             kp->last_key_state[col] = 0;
+             kp->last_key_ms[col] = 0;
+     }
+
+     /* setup input device */
+      __set_bit(EV_KEY, input->evbit);
+
+     /* Enable auto repeat feature of Linux input subsystem */
+     if (!(kp->no_autorepeat))
+             __set_bit(EV_REP, input->evbit);
+
+     input_set_capability(input, EV_MSC, MSC_SCAN);
+     input->name             = "SMSC Keypad";
+     input->phys             = "smsc_keypad/input0";
+     input->dev.parent       = &pdev->dev;
+     input->id.bustype       = BUS_HOST;
+     input->id.vendor        = 0x0001;
+     input->id.product       = 0x0001;
+     input->id.version       = 0x0003;
+
+     error = input_register_device(input);
+     if (error) {
+             dev_err(kp->dev,
+                     "Unable to register twl4030 keypad device\n");
+             goto err1;
+     }
+
+     /* Mask all GPIO interrupts (0x37-0x3B) */
+     for (addr = 0x37; addr < 0x3B; addr++)
+             smsc_write(dev, addr, 0);
+
+     /* Set all outputs high (0x05-0x09) */
+     for (addr = 0x05; addr < 0x09; addr++)
+             smsc_write(dev, addr, 0xff);
+
+     /* Clear all GPIO interrupts (0x32-0x36) */
+     for (addr = 0x32; addr < 0x36; addr++)
+             smsc_write(dev, addr, 0xff);
+
+     addr_start = 0x12;
+     for (i = 0; i <= kp->rows; i++) {
+             addr = 0x12 + i;
+             smsc_write(dev, addr, SMSC_KP_KSI);
+     }
+
+     addr_start =  0x1A;
+     for (i = 0; i <= kp->cols; i++) {
+             addr = 0x1A + i;
+             smsc_write(dev, addr, SMSC_KP_KSO);
+     }
+

Lots of magic numbers without proper description/comments.

I will try to put comments or replace the magic numbers with the
macros declared in .h file.

quoted

quoted

+     addr = SMSC_KP_INT_STAT;
+     smsc_write(dev, addr, SMSC_KP_SET_HIGH);
+
+     addr = SMSC_WKUP_CTRL;
+     smsc_write(dev, addr, SMSC_KP_SET_LOW_PWR);
+
+     addr = SMSC_KP_OUT;
+     smsc_write(dev, addr, SMSC_KSO_ALL_LOW);
+

I didn't understand why to initialize 'addr' and pass it, why can't you
directly pass it as a argument?

Actually Yes, addr can be directly replaced with the corresponding address.

quoted

quoted

+     row_shift = get_count_order(kp->cols);
+     max_keys = kp->rows << row_shift;
+
+     kp->row_shift = row_shift;
+     kp->keymap = kzalloc(max_keys * sizeof(kp->keymap[0]),
+                                     GFP_KERNEL);
+     if (!kp->keymap) {
+             dev_err(&pdev->dev, "Not enough memory for keymap\n");
+             error = -ENOMEM;
+     }
+
+     matrix_keypad_build_keymap(NULL, NULL, kp->rows,
+                     kp->cols, kp->keymap, input);
+
+     /*
+     * This ISR will always execute in kernel thread context because of
+     * the need to access the SMSC over the I2C bus.
+     */
+     ret = devm_request_threaded_irq(dev, kp->irq, NULL, do_kp_irq,
+                     IRQF_TRIGGER_FALLING | IRQF_ONESHOT, pdev->name, kp);
+     if (ret) {
+             dev_dbg(&pdev->dev, "request_irq failed for irq no=%d\n",
+                     irq);
+             goto err2;
+     }
+
+     /* Enable smsc keypad interrupts */
+     ret = smsc_write(dev, SMSC_KP_INT_MASK, 0xff);
+     if (ret < 0)
+             goto err2;
+
+     return 0;
+
+err2:
+     input_unregister_device(input);
+err1:
+     input_free_device(input);

You are not freeing memory allocated for kp->keymap. Please use devm_
variants.

True. Will do.

quoted

Thanks,
Vaibhav

quoted

+     return ret;
+}
+
+static int __devexit smsc_remove(struct platform_device *pdev)
+{
+     struct smsc_keypad *kp = platform_get_drvdata(pdev);
+     input_unregister_device(kp->input);
+
+     return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id smsc_keypad_dt_match[] = {
+     { .compatible = "smsc,keypad" },
+     {},
+};
+MODULE_DEVICE_TABLE(of, smsc_keypad_dt_match);
+#endif
+
+static struct platform_driver smsc_driver = {
+     .driver = {
+             .name   = "smsc-keypad",
+             .of_match_table = of_match_ptr(smsc_keypad_dt_match),
+             .owner  = THIS_MODULE,
+     },
+     .probe          = smsc_probe,
+     .remove         = __devexit_p(smsc_remove),
+};
+
+module_platform_driver(smsc_driver);
+
+MODULE_AUTHOR("G Kondaiah Manjunath [off-list ref]");
+MODULE_DESCRIPTION("SMSC ECE1099 Keypad driver");
+MODULE_LICENSE("GPL v2");