[PATCH v3] input: MXC: add mxc-keypad driver to support the Keypad Port present in the mxc application processors family.
Lothar Waßmann
LW at KARO-electronics.de
Wed Jan 27 05:33:04 EST 2010
Hi,
Alberto Panizzo writes:
[...]
> arch/arm/plat-mxc/include/mach/mxc_keypad.h | 18 +
> drivers/input/keyboard/Kconfig | 9 +
> drivers/input/keyboard/Makefile | 1 +
> drivers/input/keyboard/mxc_keypad.c | 516 +++++++++++++++++++++++++++
> 4 files changed, 544 insertions(+), 0 deletions(-)
> create mode 100644 arch/arm/plat-mxc/include/mach/mxc_keypad.h
> create mode 100644 drivers/input/keyboard/mxc_keypad.c
>
> diff --git a/arch/arm/plat-mxc/include/mach/mxc_keypad.h b/arch/arm/plat-mxc/include/mach/mxc_keypad.h
> new file mode 100644
> index 0000000..4509103
> --- /dev/null
> +++ b/arch/arm/plat-mxc/include/mach/mxc_keypad.h
> @@ -0,0 +1,18 @@
> +#ifndef __MACH_MXC_KEYPAD_H
> +#define __MACH_MXC_KEYPAD_H
> +
> +#include <linux/input/matrix_keypad.h>
> +
> +#define MAX_MATRIX_KEY_ROWS (8)
> +#define MAX_MATRIX_KEY_COLS (8)
> +#define MATRIX_ROW_SHIFT (3)
> +
pointless '()'
> +
> +/*
> + * Keypad Controller registers (halfword)
> + */
> +#define KPCR 0x00 /* Keypad Control Register */
> +
> +#define KPSR 0x02 /* Keypad Status Register */
> +#define KBD_STAT_KPKD (0x1 << 0) /* Key Press Interrupt Status bit */
> +#define KBD_STAT_KPKR (0x1 << 1) /* Key Release Interrupt Status bit */
> +#define KBD_STAT_KDSC (0x1 << 2) /* Key Depress Synch Chain Status bit */
> +#define KBD_STAT_KRSS (0x1 << 3) /* Key Release Synch Status bit */
> +#define KBD_STAT_KDIE (0x1 << 8) /* Key Depress Interrupt Enable Status bit */
> +#define KBD_STAT_KRIE (0x1 << 9) /* Key Release Interrupt Enable */
> +#define KBD_STAT_KPPEN (0x1 << 10) /* Keypad Clock Enable */
> +
> +#define KDDR 0x04 /* Keypad Data Direction Register */
> +#define KPDR 0x06 /* Keypad Data Register */
> +
> +#define MAX_MATRIX_KEY_NUM (MAX_MATRIX_KEY_ROWS * MAX_MATRIX_KEY_COLS)
> +
> +struct mxc_keypad {
> + struct mxc_keypad_platform_data *pdata;
> +
> + struct clk *clk;
> + struct input_dev *input_dev;
> + void __iomem *mmio_base;
> +
> + int irq;
> + struct timer_list scan_timer;
> + struct timer_list relax_timer;
> +
> +#define MXC_IRQ_KDI 1
> +#define MXC_IRQ_KRI 2
> + unsigned int irq_type;
> + int irq_since_last_change;
^
SPACE before TAB (emacs can highlight those... ;)
> +
> + /* Masks for enabled rows/cols */
> + unsigned short rows_en_mask;
> + unsigned short cols_en_mask;
> +
> + unsigned short keycodes[MAX_MATRIX_KEY_NUM];
^
dto.
> +
> + /* state row bits of each column scan */
> + unsigned short matrix_key_state[MAX_MATRIX_KEY_COLS];
^
dto.
> +};
> +
> +/* Return 0 if no changes are detected in matrix */
> +static int mxc_keypad_scan_matrix(struct mxc_keypad *keypad)
> +{
> + struct input_dev *input_dev = keypad->input_dev;
> + int row, col, changed = 0;
> + unsigned short new_state[MAX_MATRIX_KEY_COLS];
> + unsigned short reg_val;
> +
> + memset(new_state, 0, sizeof(new_state));
> +
> + for (col = 0; col < MAX_MATRIX_KEY_COLS; col++) {
> + if ((keypad->cols_en_mask & (1 << col)) == 0)
> + continue;
> + /* Discharge keypad capacitance:
> + * 2. write 1s on column data.
> + * 3. configure columns as totem-pole to discharge capacitance.
> + * 4. configure columns as open-drain.*/
> + reg_val = readw(keypad->mmio_base + KPDR);
> + reg_val |= 0xff00;
> + writew(reg_val, keypad->mmio_base + KPDR);
> +
> + reg_val = readw(keypad->mmio_base + KPCR);
> + reg_val &= ~((keypad->cols_en_mask & 0xff) << 8);
> + writew(reg_val, keypad->mmio_base + KPCR);
> +
> + udelay(2);
> +
> + reg_val = readw(keypad->mmio_base + KPCR);
> + reg_val |= (keypad->cols_en_mask & 0xff) << 8;
> + writew(reg_val, keypad->mmio_base + KPCR);
> +
> + /*
> + * 5. Write a single column to 0, others to 1.
> + * 6. Sample row inputs and save data.
> + * 7. Repeat steps 2 - 6 for remaining columns.
> + */
> + reg_val = readw(keypad->mmio_base + KPDR);
> + reg_val &= ~(1 << (8 + col));
> + writew(reg_val, keypad->mmio_base + KPDR);
> +
> + /* Delay added to avoid propagating the 0 from column to row
> + * when scanning. */
> + udelay(5);
> +
> + /* 1s in state detect a key pressure */
> + new_state[col] = (~readw(keypad->mmio_base + KPDR)) & 0x00ff;
> + }
> +
> + /* Test the state changes */
> + for (col = 0; col < MAX_MATRIX_KEY_COLS; col++) {
> + unsigned short bits_changed;
> + int code;
> +
> + if ((keypad->cols_en_mask & (1 << col)) == 0)
> + continue;
> +
> + bits_changed = keypad->matrix_key_state[col] ^ new_state[col];
> + if (bits_changed == 0)
> + continue;
> +
> + changed = 1;
> + for (row = 0; row < MAX_MATRIX_KEY_ROWS; row++) {
> + if ((keypad->rows_en_mask & (1 << row)) == 0)
> + continue;
> + if ((bits_changed & (1 << row)) == 0)
> + continue;
> +
> + code = MATRIX_SCAN_CODE(row, col, MATRIX_ROW_SHIFT);
> + input_event(input_dev, EV_MSC, MSC_SCAN, code);
> + input_report_key(input_dev, keypad->keycodes[code],
> + new_state[col] & (1 << row));
> + dev_dbg(&input_dev->dev, "Event code: %d, val: %d",
> + keypad->keycodes[code],
> + new_state[col] & (1 << row));
> + }
> + }
> + input_sync(input_dev);
> + memcpy(keypad->matrix_key_state, new_state, sizeof(new_state));
> +
> + /* Return in standby mode:
> + * 9. write 0s to columns */
> + reg_val = readw(keypad->mmio_base + KPDR);
> + reg_val &= 0x00ff;
> + writew(reg_val, keypad->mmio_base + KPDR);
> +
> + return changed;
> +}
> +
> +static void mxc_keypad_relax_timer_handler(unsigned long data)
> +{
> + struct mxc_keypad *keypad = (struct mxc_keypad *) data;
> + unsigned short reg_val;
> +
> + /* 10. Clear KPKD and KPKR status bits
> + * Set the KPKR sync chain and clear the KPKD sync chain */
> + reg_val = readw(keypad->mmio_base + KPSR);
> + reg_val |= KBD_STAT_KPKD | KBD_STAT_KPKR |
> + KBD_STAT_KDSC | KBD_STAT_KRSS;
> + writew(reg_val, keypad->mmio_base + KPSR);
> +
> + /* Re enable interrupts and clear sync reset bits.
> + * Next KDI is used for detect multiple pressures. */
> + reg_val = readw(keypad->mmio_base + KPSR);
> + reg_val &= ~(KBD_STAT_KDSC | KBD_STAT_KRSS);
> + writew(reg_val, keypad->mmio_base + KPSR);
> +
> + reg_val |= KBD_STAT_KDIE | KBD_STAT_KRIE;
> + if (keypad->irq_type == MXC_IRQ_KRI)
> + reg_val &= ~KBD_STAT_KRIE;
> + writew(reg_val, keypad->mmio_base + KPSR);
> +}
> +
> +static void mxc_keypad_scan_timer_handler(unsigned long data)
> +{
> + struct mxc_keypad *keypad = (struct mxc_keypad *) data;
> + struct input_dev *idev = keypad->input_dev;
> +
> + dev_dbg(&idev->dev, "Handling Interrupt of type %x\n",
> + keypad->irq_type);
> +
> + /* Do the scan routine and Keep track for how many time we got
> + * interrupt that make no change */
> + if (mxc_keypad_scan_matrix(keypad))
> + keypad->irq_since_last_change = 0;
> + else
> + keypad->irq_since_last_change++;
> +
> + /* If the key is pressed since too many time, relax the update period */
> + if (keypad->irq_since_last_change > 2)
> + mod_timer(&keypad->relax_timer,
> + jiffies + msecs_to_jiffies(60));
> + else
> + mxc_keypad_relax_timer_handler((unsigned long) keypad);
> +}
> +
> +static irqreturn_t mxc_keypad_irq_handler(int irq, void *dev_id)
> +{
> + struct mxc_keypad *keypad = dev_id;
> + struct mxc_keypad_platform_data *pdata = keypad->pdata;
> + unsigned short reg_val;
> +
> + /* Disable every keypad interrupt */
> + reg_val = readw(keypad->mmio_base + KPSR);
> + reg_val &= ~(KBD_STAT_KRIE | KBD_STAT_KDIE);
> + writew(reg_val, keypad->mmio_base + KPSR);
> +
> + keypad->irq_type = reg_val & KBD_STAT_KPKD ?
> + MXC_IRQ_KDI : MXC_IRQ_KRI;
> +
> + /* Schedule the scanning procedure */
> + mod_timer(&keypad->scan_timer,
> + jiffies + msecs_to_jiffies(pdata->debounce_ms));
> +
> + return IRQ_HANDLED;
> +}
> +
> +static void mxc_keypad_config(struct mxc_keypad *keypad)
> +{
> + unsigned short reg_val;
> +
> + /* Enable number of rows in keypad (KPCR[7:0])
> + * Configure keypad columns as open-drain (KPCR[15:8])
> + */
> + reg_val = readw(keypad->mmio_base + KPCR);
> + reg_val |= keypad->rows_en_mask & 0xff; /* rows */
> + reg_val |= (keypad->cols_en_mask & 0xff) << 8; /* cols */
> + writew(reg_val, keypad->mmio_base + KPCR);
> +
> + /* Write 0's to KPDR[15:8] (Colums)*/
> + reg_val = readw(keypad->mmio_base + KPDR);
> + reg_val &= 0x00ff;
> + writew(reg_val, keypad->mmio_base + KPDR);
> +
> + /* Configure columns as output, rows as input (KDDR[15:0]) */
> + reg_val = readw(keypad->mmio_base + KDDR);
> + reg_val |= 0xff00;
> + reg_val &= 0xff00;
>
This is effectively the same as: 'reg_val = 0xff00;' which makes the
readw() above pointless. Was this really intended?
> + writew(reg_val, keypad->mmio_base + KDDR);
> +
> + /* Clear Key Depress and Key Release status bit.
> + * Clear synchronizer chain.
> + * */
> + reg_val = readw(keypad->mmio_base + KPSR);
> + reg_val |= KBD_STAT_KPKR | KBD_STAT_KPKD |
> + KBD_STAT_KDSC | KBD_STAT_KRSS;
> + writew(reg_val, keypad->mmio_base + KPSR);
> +
> + /* Set the KDIE control bit, and clear the KRIE control bit
> + * (avoid false release events). */
> + reg_val |= KBD_STAT_KDIE;
> + reg_val &= ~KBD_STAT_KRIE;
> + writew(reg_val, keypad->mmio_base + KPSR);
> +}
> +
> +static void mxc_keypad_inhibit(struct mxc_keypad *keypad)
> +{
> + unsigned short reg_val;
> +
> + /* Colums as open drain and disable rows */
> + writew(0xff00, keypad->mmio_base + KPCR);
> +
> + /* Clear the KPKD status flag and synchronizer chain.
> + * Clear KDIE control bit and KRIE control bit.
> + */
> + reg_val = readw(keypad->mmio_base + KPSR);
> + reg_val |= KBD_STAT_KPKD | KBD_STAT_KDSC;
> + reg_val &= ~(KBD_STAT_KRIE | KBD_STAT_KDIE);
> + writew(reg_val, keypad->mmio_base + KPSR);
> +}
> +
> +static int mxc_keypad_open(struct input_dev *dev)
> +{
> + struct mxc_keypad *keypad = input_get_drvdata(dev);
> +
> + dev_dbg(&dev->dev, "%s\n", __func__);
> +
> + /* Enable unit clock */
> + clk_enable(keypad->clk);
> + mxc_keypad_config(keypad);
> +
> + /* Sanity control, not all the rows must be to 0s now. */
> + if ((readw(keypad->mmio_base + KPDR) & keypad->rows_en_mask) == 0) {
> + dev_err(&dev->dev, "Too much keys pressed for now, "
> + "control pins initialisation\n");
>
It helps grepping for a message, if it is not split into multiple
lines.
> + goto open_err;
> + }
> +
> + return 0;
> +
> +open_err:
> + mxc_keypad_inhibit(keypad);
> + return -EIO;
> +}
> +
> +static void mxc_keypad_close(struct input_dev *dev)
> +{
> + struct mxc_keypad *keypad = input_get_drvdata(dev);
> +
> + dev_dbg(&dev->dev, "%s\n", __func__);
> +
> + mxc_keypad_inhibit(keypad);
> +
> + /* Disable clock unit */
> + clk_disable(keypad->clk);
> +}
> +
> +static int __devinit mxc_keypad_probe(struct platform_device *pdev)
> +{
> + struct mxc_keypad_platform_data *pdata = pdev->dev.platform_data;
> + struct mxc_keypad *keypad;
> + struct input_dev *input_dev;
> + struct resource *res;
> + int irq, error, i;
> + const struct matrix_keymap_data *keymap_data;
> +
> + if (pdata == NULL) {
> + dev_err(&pdev->dev, "no platform data defined\n");
> + return -EINVAL;
> + }
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq < 0) {
> + dev_err(&pdev->dev, "failed to get keypad irq\n");
> + return -ENXIO;
> + }
>
This should be -ENODEV.
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (res == NULL) {
> + dev_err(&pdev->dev, "failed to get I/O memory\n");
> + return -ENXIO;
>
same as above.
> + }
> +
> + res = request_mem_region(res->start, resource_size(res), pdev->name);
> + if (res == NULL) {
> + dev_err(&pdev->dev, "failed to request I/O memory\n");
> + return -EBUSY;
> + }
> +
> + input_dev = input_allocate_device();
> + if (!input_dev) {
> + dev_err(&pdev->dev, "failed to allocate the input device\n");
> + error = -ENOMEM;
> + goto failed_rel_mem;
> + }
> +
> + keypad = kzalloc(sizeof(struct mxc_keypad), GFP_KERNEL);
> + if (!keypad) {
> + dev_err(&pdev->dev, "not enough memory for driver data\n");
> + error = -ENOMEM;
> + goto failed_free_input;
> + }
> +
> + keypad->pdata = pdata;
> + keypad->input_dev = input_dev;
> + keypad->irq = irq;
> +
> + keypad->mmio_base = ioremap(res->start, resource_size(res));
> + if (keypad->mmio_base == NULL) {
> + dev_err(&pdev->dev, "failed to remap I/O memory\n");
> + error = -ENXIO;
>
-ENOMEM;
> + goto failed_free_priv;
> + }
> +
> + keypad->clk = clk_get(NULL, "kpp");
>
clk_get(&pdev->dev, "kpp");
> + if (IS_ERR(keypad->clk)) {
> + dev_err(&pdev->dev, "failed to get keypad clock\n");
> + error = PTR_ERR(keypad->clk);
> + goto failed_unmap;
> + }
> +
> + /*
> + * Search for rows and cols enabled
> + */
> + keymap_data = pdata->keymap_data;
> + for (i = 0; i < keymap_data->keymap_size; i++) {
> + keypad->rows_en_mask |= 1 << KEY_ROW(keymap_data->keymap[i]);
> + keypad->cols_en_mask |= 1 << KEY_COL(keymap_data->keymap[i]);
> + }
> +
> + if (keypad->rows_en_mask > ((1 << MAX_MATRIX_KEY_ROWS) - 1) ||
> + keypad->cols_en_mask > ((1 << MAX_MATRIX_KEY_COLS) - 1)) {
> + dev_err(&pdev->dev, "Invalid key data (too rows or colums)\n");
> + error = -EINVAL;
> + goto failed_clock_put;
> + }
> + dev_dbg(&pdev->dev, "enabled rows mask: %x\n", keypad->rows_en_mask);
> + dev_dbg(&pdev->dev, "enabled cols mask: %x\n", keypad->cols_en_mask);
> +
> + /* Init Keypad timers */
> + init_timer(&keypad->scan_timer);
> + keypad->scan_timer.function = mxc_keypad_scan_timer_handler;
> + keypad->scan_timer.data = (unsigned long) keypad;
> +
> + init_timer(&keypad->relax_timer);
> + keypad->relax_timer.function = mxc_keypad_relax_timer_handler;
> + keypad->relax_timer.data = (unsigned long) keypad;
> +
> + /* Init the Input device */
> + input_dev->name = pdev->name;
> + input_dev->id.bustype = BUS_HOST;
> + input_dev->dev.parent = &pdev->dev;
> + input_dev->open = mxc_keypad_open;
> + input_dev->close = mxc_keypad_close;
> + input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
> + input_dev->keycode = keypad->keycodes;
> + input_dev->keycodesize = sizeof(keypad->keycodes[0]);
> + input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
> +
> + matrix_keypad_build_keymap(pdata->keymap_data, MATRIX_ROW_SHIFT,
> + keypad->keycodes, input_dev->keybit);
> +
> + input_set_capability(input_dev, EV_MSC, MSC_SCAN);
> + input_set_drvdata(input_dev, keypad);
> +
> + error = request_irq(irq, mxc_keypad_irq_handler, IRQF_DISABLED,
> + pdev->name, keypad);
> + if (error) {
> + dev_err(&pdev->dev, "failed to request IRQ\n");
> + goto failed_clock_put;
> + }
> +
> + /* Register the input device */
> + error = input_register_device(input_dev);
> + if (error) {
> + dev_err(&pdev->dev, "failed to register input device\n");
> + goto failed_free_irq;
> + }
> +
> + platform_set_drvdata(pdev, keypad);
> + device_init_wakeup(&pdev->dev, 1);
> +
> + dev_info(&pdev->dev, "device probed\n");
> +
> + return 0;
> +
> +failed_free_irq:
> + free_irq(irq, pdev);
> +failed_clock_put:
> + clk_put(keypad->clk);
> +failed_unmap:
> + iounmap(keypad->mmio_base);
> +failed_free_priv:
> + kfree(keypad);
> +failed_free_input:
> + input_free_device(input_dev);
> +failed_rel_mem:
> + release_mem_region(res->start, resource_size(res));
> + return error;
> +}
> +
> +static int __devexit mxc_keypad_remove(struct platform_device *pdev)
> +{
> + struct mxc_keypad *keypad = platform_get_drvdata(pdev);
> + struct resource *res;
> +
> + platform_set_drvdata(pdev, NULL);
> +
> + free_irq(keypad->irq, keypad);
> + clk_put(keypad->clk);
> + del_timer_sync(&keypad->scan_timer);
> + del_timer_sync(&keypad->relax_timer);
> +
> + input_unregister_device(keypad->input_dev);
> +
> + iounmap(keypad->mmio_base);
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + release_mem_region(res->start, resource_size(res));
> +
> + kfree(keypad);
> +
> + dev_info(&pdev->dev, "device removed\n");
> +
> + return 0;
> +}
> +
> +static struct platform_driver mxc_keypad_driver = {
> + .driver = {
> + .name = "mxc-keypad",
> + .owner = THIS_MODULE,
> + },
> + .probe = mxc_keypad_probe,
> + .remove = __devexit_p(mxc_keypad_remove),
> +};
> +
> +static int __init mxc_keypad_init(void)
> +{
> + return platform_driver_register(&mxc_keypad_driver);
> +}
> +
> +static void __exit mxc_keypad_exit(void)
> +{
> + platform_driver_unregister(&mxc_keypad_driver);
> +}
> +
> +module_init(mxc_keypad_init);
> +module_exit(mxc_keypad_exit);
> +
> +MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto at gmail.com>");
> +MODULE_DESCRIPTION("MXC Keypad Port Driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform:mxc-keypad");
> --
> 1.6.3.3
>
>
>
>
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> linux-arm-kernel at lists.infradead.org
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Lothar Waßmann
--
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