input/keyboard/imx_keypad.c

3 // Driver for the IMX keypad port.
79 static void imx_keypad_scan_matrix(struct imx_keypad *keypad,
86 		if ((keypad->cols_en_mask & (1 << col)) == 0)
89 		 * Discharge keypad capacitance:
94 		reg_val = readw(keypad->mmio_base + KPDR);
96 		writew(reg_val, keypad->mmio_base + KPDR);
98 		reg_val = readw(keypad->mmio_base + KPCR);
99 		reg_val &= ~((keypad->cols_en_mask & 0xff) << 8);
100 		writew(reg_val, keypad->mmio_base + KPCR);
104 		reg_val = readw(keypad->mmio_base + KPCR);
105 		reg_val |= (keypad->cols_en_mask & 0xff) << 8;
106 		writew(reg_val, keypad->mmio_base + KPCR);
113 		reg_val = readw(keypad->mmio_base + KPDR);
115 		writew(reg_val, keypad->mmio_base + KPDR);
127 		reg_val = readw(keypad->mmio_base + KPDR);
128 		matrix_volatile_state[col] = (~reg_val) & keypad->rows_en_mask;
135 	reg_val = readw(keypad->mmio_base + KPDR);
137 	writew(reg_val, keypad->mmio_base + KPDR);
142  * keypad->matrix_stable_state and fire events if changes are detected.
144 static void imx_keypad_fire_events(struct imx_keypad *keypad,
147 	struct input_dev *input_dev = keypad->input_dev;
154 		if ((keypad->cols_en_mask & (1 << col)) == 0)
157 		bits_changed = keypad->matrix_stable_state[col] ^
164 			if ((keypad->rows_en_mask & (1 << row)) == 0)
171 			input_report_key(input_dev, keypad->keycodes[code],
174 				keypad->keycodes[code],
186 	struct imx_keypad *keypad = from_timer(keypad, t, check_matrix_timer);
194 	imx_keypad_scan_matrix(keypad, matrix_volatile_state);
198 		if ((keypad->cols_en_mask & (1 << i)) == 0)
201 		if (keypad->matrix_unstable_state[i] ^ matrix_volatile_state[i]) {
210 	 *    keypad->matrix_unstable_state.
215 		memcpy(keypad->matrix_unstable_state, matrix_volatile_state,
217 		keypad->stable_count = 0;
219 		keypad->stable_count++;
225 	if (keypad->stable_count < IMX_KEYPAD_SCANS_FOR_STABILITY) {
226 		mod_timer(&keypad->check_matrix_timer,
234 	 * (keypad->stable_count > IMX_KEYPAD_SCANS_FOR_STABILITY) all
237 	if (keypad->stable_count == IMX_KEYPAD_SCANS_FOR_STABILITY) {
238 		imx_keypad_fire_events(keypad, matrix_volatile_state);
240 		memcpy(keypad->matrix_stable_state, matrix_volatile_state,
259 		reg_val = readw(keypad->mmio_base + KPSR);
261 		writew(reg_val, keypad->mmio_base + KPSR);
263 		reg_val = readw(keypad->mmio_base + KPSR);
266 		writew(reg_val, keypad->mmio_base + KPSR);
274 		mod_timer(&keypad->check_matrix_timer,
277 		reg_val = readw(keypad->mmio_base + KPSR);
279 		writew(reg_val, keypad->mmio_base + KPSR);
281 		reg_val = readw(keypad->mmio_base + KPSR);
284 		writew(reg_val, keypad->mmio_base + KPSR);
290 	struct imx_keypad *keypad = dev_id;
293 	reg_val = readw(keypad->mmio_base + KPSR);
299 	writew(reg_val, keypad->mmio_base + KPSR);
301 	if (keypad->enabled) {
303 		keypad->stable_count = 0;
306 		mod_timer(&keypad->check_matrix_timer,
313 static void imx_keypad_config(struct imx_keypad *keypad)
319 	 * Configure keypad columns as open-drain (KPCR[15:8])
321 	reg_val = readw(keypad->mmio_base + KPCR);
322 	reg_val |= keypad->rows_en_mask & 0xff;		/* rows */
323 	reg_val |= (keypad->cols_en_mask & 0xff) << 8;	/* cols */
324 	writew(reg_val, keypad->mmio_base + KPCR);
327 	reg_val = readw(keypad->mmio_base + KPDR);
329 	writew(reg_val, keypad->mmio_base + KPDR);
332 	writew(0xff00, keypad->mmio_base + KDDR);
338 	reg_val = readw(keypad->mmio_base + KPSR);
341 	writew(reg_val, keypad->mmio_base + KPSR);
346 	writew(reg_val, keypad->mmio_base + KPSR);
349 static void imx_keypad_inhibit(struct imx_keypad *keypad)
354 	reg_val = readw(keypad->mmio_base + KPSR);
357 	writew(reg_val, keypad->mmio_base + KPSR);
360 	reg_val = (keypad->cols_en_mask & 0xff) << 8;
361 	writew(reg_val, keypad->mmio_base + KPCR);
366 	struct imx_keypad *keypad = input_get_drvdata(dev);
370 	/* Mark keypad as being inactive */
371 	keypad->enabled = false;
372 	synchronize_irq(keypad->irq);
373 	del_timer_sync(&keypad->check_matrix_timer);
375 	imx_keypad_inhibit(keypad);
378 	clk_disable_unprepare(keypad->clk);
383 	struct imx_keypad *keypad = input_get_drvdata(dev);
389 	error = clk_prepare_enable(keypad->clk);
394 	keypad->enabled = true;
396 	imx_keypad_config(keypad);
399 	if ((readw(keypad->mmio_base + KPDR) & keypad->rows_en_mask) == 0) {
420 	struct imx_keypad *keypad;
434 	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
435 	if (!keypad) {
440 	keypad->input_dev = input_dev;
441 	keypad->irq = irq;
442 	keypad->stable_count = 0;
444 	timer_setup(&keypad->check_matrix_timer,
447 	keypad->mmio_base = devm_platform_ioremap_resource(pdev, 0);
448 	if (IS_ERR(keypad->mmio_base))
449 		return PTR_ERR(keypad->mmio_base);
451 	keypad->clk = devm_clk_get(&pdev->dev, NULL);
452 	if (IS_ERR(keypad->clk)) {
453 		dev_err(&pdev->dev, "failed to get keypad clock\n");
454 		return PTR_ERR(keypad->clk);
467 					   keypad->keycodes, input_dev);
477 			if (keypad->keycodes[i] != KEY_RESERVED) {
478 				keypad->rows_en_mask |= 1 << row;
479 				keypad->cols_en_mask |= 1 << col;
483 	dev_dbg(&pdev->dev, "enabled rows mask: %x\n", keypad->rows_en_mask);
484 	dev_dbg(&pdev->dev, "enabled cols mask: %x\n", keypad->cols_en_mask);
488 	input_set_drvdata(input_dev, keypad);
490 	/* Ensure that the keypad will stay dormant until opened */
491 	error = clk_prepare_enable(keypad->clk);
494 	imx_keypad_inhibit(keypad);
495 	clk_disable_unprepare(keypad->clk);
498 			    pdev->name, keypad);
511 	platform_set_drvdata(pdev, keypad);
575 		.name	= "imx-keypad",
586 MODULE_ALIAS("platform:imx-keypad");