media: rc: add zx-irdec remote control driver

It adds the remote control driver and corresponding keymap file for
IRDEC block found on ZTE ZX family SoCs.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

1 files changed, 183 insertions, 0 deletions

diff --git a/drivers/media/rc/zx-irdec.c b/drivers/media/rc/zx-irdec.c
new file mode 100644
index 000000000000..9452bac9262c
--- /dev/null
+++ b/drivers/media/rc/zx-irdec.c
@@ -0,0 +1,183 @@
+/*
+ * Copyright (C) 2017 Sanechips Technology Co., Ltd.
+ * Copyright 2017 Linaro Ltd.
+ *
+ * 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/device.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+#include <media/rc-core.h>
+
+#define DRIVER_NAME		"zx-irdec"
+
+#define ZX_IR_ENABLE		0x04
+#define ZX_IREN			BIT(0)
+#define ZX_IR_CTRL		0x08
+#define ZX_DEGL_MASK		GENMASK(21, 20)
+#define ZX_DEGL_VALUE(x)	(((x) << 20) & ZX_DEGL_MASK)
+#define ZX_WDBEGIN_MASK		GENMASK(18, 8)
+#define ZX_WDBEGIN_VALUE(x)	(((x) << 8) & ZX_WDBEGIN_MASK)
+#define ZX_IR_INTEN		0x10
+#define ZX_IR_INTSTCLR		0x14
+#define ZX_IR_CODE		0x30
+#define ZX_IR_CNUM		0x34
+#define ZX_NECRPT		BIT(16)
+
+struct zx_irdec {
+	void __iomem *base;
+	struct rc_dev *rcd;
+};
+
+static void zx_irdec_set_mask(struct zx_irdec *irdec, unsigned int reg,
+			      u32 mask, u32 value)
+{
+	u32 data;
+
+	data = readl(irdec->base + reg);
+	data &= ~mask;
+	data |= value & mask;
+	writel(data, irdec->base + reg);
+}
+
+static irqreturn_t zx_irdec_irq(int irq, void *dev_id)
+{
+	struct zx_irdec *irdec = dev_id;
+	u8 address, not_address;
+	u8 command, not_command;
+	u32 rawcode, scancode;
+	enum rc_type rc_type;
+
+	/* Clear interrupt */
+	writel(1, irdec->base + ZX_IR_INTSTCLR);
+
+	/* Check repeat frame */
+	if (readl(irdec->base + ZX_IR_CNUM) & ZX_NECRPT) {
+		rc_repeat(irdec->rcd);
+		goto done;
+	}
+
+	rawcode = readl(irdec->base + ZX_IR_CODE);
+	not_command = (rawcode >> 24) & 0xff;
+	command = (rawcode >> 16) & 0xff;
+	not_address = (rawcode >> 8) & 0xff;
+	address = rawcode & 0xff;
+
+	scancode = ir_nec_bytes_to_scancode(address, not_address,
+					    command, not_command,
+					    &rc_type);
+	rc_keydown(irdec->rcd, rc_type, scancode, 0);
+
+done:
+	return IRQ_HANDLED;
+}
+
+static int zx_irdec_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct zx_irdec *irdec;
+	struct resource *res;
+	struct rc_dev *rcd;
+	int irq;
+	int ret;
+
+	irdec = devm_kzalloc(dev, sizeof(*irdec), GFP_KERNEL);
+	if (!irdec)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	irdec->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(irdec->base))
+		return PTR_ERR(irdec->base);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	rcd = devm_rc_allocate_device(dev, RC_DRIVER_SCANCODE);
+	if (!rcd) {
+		dev_err(dev, "failed to allocate rc device\n");
+		return -ENOMEM;
+	}
+
+	irdec->rcd = rcd;
+
+	rcd->priv = irdec;
+	rcd->input_phys = DRIVER_NAME "/input0";
+	rcd->input_id.bustype = BUS_HOST;
+	rcd->map_name = RC_MAP_ZX_IRDEC;
+	rcd->allowed_protocols = RC_BIT_NEC | RC_BIT_NECX | RC_BIT_NEC32;
+	rcd->driver_name = DRIVER_NAME;
+	rcd->device_name = DRIVER_NAME;
+
+	platform_set_drvdata(pdev, irdec);
+
+	ret = devm_rc_register_device(dev, rcd);
+	if (ret) {
+		dev_err(dev, "failed to register rc device\n");
+		return ret;
+	}
+
+	ret = devm_request_irq(dev, irq, zx_irdec_irq, 0, NULL, irdec);
+	if (ret) {
+		dev_err(dev, "failed to request irq\n");
+		return ret;
+	}
+
+	/*
+	 * Initialize deglitch level and watchdog counter beginner as
+	 * recommended by vendor BSP code.
+	 */
+	zx_irdec_set_mask(irdec, ZX_IR_CTRL, ZX_DEGL_MASK, ZX_DEGL_VALUE(0));
+	zx_irdec_set_mask(irdec, ZX_IR_CTRL, ZX_WDBEGIN_MASK,
+			  ZX_WDBEGIN_VALUE(0x21c));
+
+	/* Enable interrupt */
+	writel(1, irdec->base + ZX_IR_INTEN);
+
+	/* Enable the decoder */
+	zx_irdec_set_mask(irdec, ZX_IR_ENABLE, ZX_IREN, ZX_IREN);
+
+	return 0;
+}
+
+static int zx_irdec_remove(struct platform_device *pdev)
+{
+	struct zx_irdec *irdec = platform_get_drvdata(pdev);
+
+	/* Disable the decoder */
+	zx_irdec_set_mask(irdec, ZX_IR_ENABLE, ZX_IREN, 0);
+
+	/* Disable interrupt */
+	writel(0, irdec->base + ZX_IR_INTEN);
+
+	return 0;
+}
+
+static const struct of_device_id zx_irdec_match[] = {
+	{ .compatible = "zte,zx296718-irdec" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, zx_irdec_match);
+
+static struct platform_driver zx_irdec_driver = {
+	.probe = zx_irdec_probe,
+	.remove = zx_irdec_remove,
+	.driver = {
+		.name = DRIVER_NAME,
+		.of_match_table	= zx_irdec_match,
+	},
+};
+module_platform_driver(zx_irdec_driver);
+
+MODULE_DESCRIPTION("ZTE ZX IR remote control driver");
+MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>");
+MODULE_LICENSE("GPL v2");