[PATCH v2 0/2] media: rc: add support for IR receiver on MT7623 SoC

[PATCH v2 0/2] media: rc: add support for IR receiver on MT7623 SoC

[sean.wang]

From: Sean Wang <sean.wang@mediatek.com>

This patchset introduces consumer IR (CIR) support on MT7623 SoC 
that also works on other similar SoCs and implements raw mode for
more compatibility with different protocols. The driver simply
reports the duration of pulses and spaces to rc-core logic to
decode.

Changes since v1:
- change compatible string from "mediatek,mt7623-ir" into 
"mediatek,mt7623-cir"
- use KBUILD_MODNAME to provide consistent device name used in driver.
- remove unused fields in struct mtk_ir.
- use synchronize_irq to give protection between IRQ handler and 
remove handler.
- use devm_rc_allocate_device based on Andi Shyti's work.
- simplify error handling patch with devm_rc_register_device and devm_rc_allocate_device.
- remove unused spinlock.
- add comments about hardware limitation and related workarounds.
- enhance the caculation of sampling period for easiler assigned specific 
value.
- refine git description.
- fix IR message handling between IR hardware and rc-core.

Sean Wang (2):
  Documentation: devicetree: Add document bindings for mtk-cir
  media: rc: add driver for IR remote receiver on MT7623 SoC

 .../devicetree/bindings/media/mtk-cir.txt          |  24 ++
 drivers/media/rc/Kconfig                           |  11 +
 drivers/media/rc/Makefile                          |   1 +
 drivers/media/rc/mtk-cir.c                         | 326 +++++++++++++++++++++
 4 files changed, 362 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/mtk-cir.txt
 create mode 100644 drivers/media/rc/mtk-cir.c

-- 
2.7.4

[PATCH v2 1/2] Documentation: devicetree: Add document bindings for mtk-cir

[sean.wang]

From: Sean Wang <sean.wang@mediatek.com>

This patch adds documentation for devicetree bindings for
Mediatek consumer IR controller.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
---
 .../devicetree/bindings/media/mtk-cir.txt          | 24 ++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/mtk-cir.txt

diff --git a/Documentation/devicetree/bindings/media/mtk-cir.txt b/Documentation/devicetree/bindings/media/mtk-cir.txt
new file mode 100644
index 0000000..3850cbd
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/mtk-cir.txt
@@ -0,0 +1,24 @@
+Device-Tree bindings for Mediatek consumer IR controller found in
+Mediatek SoC family
+
+Required properties:
+- compatible	    : "mediatek,mt7623-cir"
+- clocks	    : list of clock specifiers, corresponding to
+		      entries in clock-names property;
+- clock-names	    : should contain "clk" entries;
+- interrupts	    : should contain IR IRQ number;
+- reg		    : should contain IO map address for IR.
+
+Optional properties:
+- linux,rc-map-name : Remote control map name.
+
+Example:
+
+cir: cir@10013000 {
+	compatible = "mediatek,mt7623-cir";
+	reg = <0 0x10013000 0 0x1000>;
+	interrupts = <GIC_SPI 87 IRQ_TYPE_LEVEL_LOW>;
+	clocks = <&infracfg CLK_INFRA_IRRX>;
+	clock-names = "clk";
+	linux,rc-map-name = "rc-rc6-mce";
+};
-- 
2.7.4

[PATCH v2 2/2] media: rc: add driver for IR remote receiver on MT7623 SoC

[sean.wang]

From: Sean Wang <sean.wang@mediatek.com>

This patch adds driver for IR controller on MT7623 SoC.
and should also work on similar Mediatek SoC. Currently
testing successfully on NEC and SONY remote controller
only but it should work on others (lirc, rc-5 and rc-6).

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Reviewed-by: Sean Young <sean@mess.org>
---
 drivers/media/rc/Kconfig   |  11 ++
 drivers/media/rc/Makefile  |   1 +
 drivers/media/rc/mtk-cir.c | 326 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 338 insertions(+)
 create mode 100644 drivers/media/rc/mtk-cir.c

diff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig
index 629e8ca..9228479 100644
--- a/drivers/media/rc/Kconfig
+++ b/drivers/media/rc/Kconfig
@@ -235,6 +235,17 @@ config IR_MESON
 	   To compile this driver as a module, choose M here: the
 	   module will be called meson-ir.
 
+config IR_MTK
+	tristate "Mediatek IR remote receiver"
+	depends on RC_CORE
+	depends on ARCH_MEDIATEK || COMPILE_TEST
+	---help---
+	   Say Y if you want to use the IR remote receiver available
+	   on Mediatek SoCs.
+
+	   To compile this driver as a module, choose M here: the
+	   module will be called mtk-cir.
+
 config IR_NUVOTON
 	tristate "Nuvoton w836x7hg Consumer Infrared Transceiver"
 	depends on PNP
diff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile
index 3a984ee..a78570b 100644
--- a/drivers/media/rc/Makefile
+++ b/drivers/media/rc/Makefile
@@ -38,3 +38,4 @@ obj-$(CONFIG_RC_ST) += st_rc.o
 obj-$(CONFIG_IR_SUNXI) += sunxi-cir.o
 obj-$(CONFIG_IR_IMG) += img-ir/
 obj-$(CONFIG_IR_SERIAL) += serial_ir.o
+obj-$(CONFIG_IR_MTK) += mtk-cir.o
diff --git a/drivers/media/rc/mtk-cir.c b/drivers/media/rc/mtk-cir.c
new file mode 100644
index 0000000..f752f63
--- /dev/null
+++ b/drivers/media/rc/mtk-cir.c
@@ -0,0 +1,326 @@
+/*
+ * Driver for Mediatek IR Receiver Controller
+ *
+ * Copyright (C) 2017 Sean Wang <sean.wang@mediatek.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/reset.h>
+#include <media/rc-core.h>
+
+#define MTK_IR_DEV KBUILD_MODNAME
+
+/* Register to enable PWM and IR */
+#define MTK_CONFIG_HIGH_REG       0x0c
+/* Enable IR pulse width detection */
+#define MTK_PWM_EN		  BIT(13)
+/* Enable IR hardware function */
+#define MTK_IR_EN		  BIT(0)
+
+/* Register to setting sample period */
+#define MTK_CONFIG_LOW_REG        0x10
+/* Field to set sample period */
+#define CHK_PERIOD		  DIV_ROUND_CLOSEST(MTK_IR_SAMPLE,  \
+						    MTK_IR_CLK_PERIOD)
+#define MTK_CHK_PERIOD            (((CHK_PERIOD) << 8) & (GENMASK(20, 8)))
+#define MTK_CHK_PERIOD_MASK	  (GENMASK(20, 8))
+
+/* Register to clear state of state machine */
+#define MTK_IRCLR_REG             0x20
+/* Bit to restart IR receiving */
+#define MTK_IRCLR		  BIT(0)
+
+/* Register containing pulse width data */
+#define MTK_CHKDATA_REG(i)        (0x88 + 4 * (i))
+#define MTK_WIDTH_MASK		  (GENMASK(7, 0))
+
+/* Register to enable IR interrupt */
+#define MTK_IRINT_EN_REG          0xcc
+/* Bit to enable interrupt */
+#define MTK_IRINT_EN		  BIT(0)
+
+/* Register to ack IR interrupt */
+#define MTK_IRINT_CLR_REG         0xd0
+/* Bit to clear interrupt status */
+#define MTK_IRINT_CLR		  BIT(0)
+
+/* Maximum count of samples */
+#define MTK_MAX_SAMPLES		  0xff
+/* Indicate the end of IR message */
+#define MTK_IR_END(v, p)	  ((v) == MTK_MAX_SAMPLES && (p) == 0)
+/* Number of registers to record the pulse width */
+#define MTK_CHKDATA_SZ		  17
+/* Source clock frequency */
+#define MTK_IR_BASE_CLK		  273000000
+/* Frequency after IR internal divider */
+#define MTK_IR_CLK_FREQ		  (MTK_IR_BASE_CLK / 4)
+/* Period for MTK_IR_CLK in ns*/
+#define MTK_IR_CLK_PERIOD	  DIV_ROUND_CLOSEST(1000000000ul,  \
+						    MTK_IR_CLK_FREQ)
+/* Sample period in ns */
+#define MTK_IR_SAMPLE		  (MTK_IR_CLK_PERIOD * 0xc00)
+
+/* struct mtk_ir -	This is the main datasructure for holding the state
+ *			of the driver
+ * @dev:		The device pointer
+ * @rc:			The rc instrance
+ * @irq:		The IRQ that we are using
+ * @base:		The mapped register i/o base
+ * @clk:		The clock that we are using
+ */
+struct mtk_ir {
+	struct device	*dev;
+	struct rc_dev	*rc;
+	void __iomem	*base;
+	int		irq;
+	struct clk	*clk;
+};
+
+static void mtk_w32_mask(struct mtk_ir *ir, u32 val, u32 mask, unsigned int reg)
+{
+	u32 tmp;
+
+	tmp = __raw_readl(ir->base + reg);
+	tmp = (tmp & ~mask) | val;
+	__raw_writel(tmp, ir->base + reg);
+}
+
+static void mtk_w32(struct mtk_ir *ir, u32 val, unsigned int reg)
+{
+	__raw_writel(val, ir->base + reg);
+}
+
+static u32 mtk_r32(struct mtk_ir *ir, unsigned int reg)
+{
+	return __raw_readl(ir->base + reg);
+}
+
+static inline void mtk_irq_disable(struct mtk_ir *ir, u32 mask)
+{
+	u32 val;
+
+	val = mtk_r32(ir, MTK_IRINT_EN_REG);
+	mtk_w32(ir, val & ~mask, MTK_IRINT_EN_REG);
+}
+
+static inline void mtk_irq_enable(struct mtk_ir *ir, u32 mask)
+{
+	u32 val;
+
+	val = mtk_r32(ir, MTK_IRINT_EN_REG);
+	mtk_w32(ir, val | mask, MTK_IRINT_EN_REG);
+}
+
+static irqreturn_t mtk_ir_irq(int irqno, void *dev_id)
+{
+	struct mtk_ir *ir = dev_id;
+	u8  wid = 0;
+	u32 i, j, val;
+	DEFINE_IR_RAW_EVENT(rawir);
+
+	mtk_irq_disable(ir, MTK_IRINT_EN);
+
+	/* Reset decoder state machine */
+	ir_raw_event_reset(ir->rc);
+
+	/* First message must be pulse */
+	rawir.pulse = false;
+
+	/* Handle all pulse and space IR controller captures */
+	for (i = 0 ; i < MTK_CHKDATA_SZ ; i++) {
+		val = mtk_r32(ir, MTK_CHKDATA_REG(i));
+		dev_dbg(ir->dev, "@reg%d=0x%08x\n", i, val);
+
+		for (j = 0 ; j < 4 ; j++) {
+			wid = (val & (MTK_WIDTH_MASK << j * 8)) >> j * 8;
+			rawir.pulse = !rawir.pulse;
+			rawir.duration = wid * (MTK_IR_SAMPLE + 1);
+			ir_raw_event_store_with_filter(ir->rc, &rawir);
+		}
+	}
+
+	/* The maximum number of edges the IR controller can
+	 * hold is MTK_CHKDATA_SZ * 4. So if received IR messages
+	 * is over the limit, the last incomplete IR message would
+	 * be appended trailing space and still would be sent into
+	 * ir-rc-raw to decode. That helps it is possible that it
+	 * has enough information to decode a scancode even if the
+	 * trailing end of the message is missing.
+	 */
+	if (!MTK_IR_END(wid, rawir.pulse)) {
+		rawir.pulse = false;
+		rawir.duration = MTK_MAX_SAMPLES * (MTK_IR_SAMPLE + 1);
+		ir_raw_event_store_with_filter(ir->rc, &rawir);
+	}
+
+	ir_raw_event_handle(ir->rc);
+
+	/* Restart controller for the next receive */
+	mtk_w32_mask(ir, 0x1, MTK_IRCLR, MTK_IRCLR_REG);
+
+	/* Clear interrupt status */
+	mtk_w32_mask(ir, 0x1, MTK_IRINT_CLR, MTK_IRINT_CLR_REG);
+
+	/* Enable interrupt */
+	mtk_irq_enable(ir, MTK_IRINT_EN);
+
+	return IRQ_HANDLED;
+}
+
+static int mtk_ir_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *dn = dev->of_node;
+	struct resource *res;
+	struct mtk_ir *ir;
+	u32 val;
+	int ret = 0;
+	const char *map_name;
+
+	ir = devm_kzalloc(dev, sizeof(struct mtk_ir), GFP_KERNEL);
+	if (!ir)
+		return -ENOMEM;
+
+	ir->dev = dev;
+
+	if (!of_device_is_compatible(dn, "mediatek,mt7623-cir"))
+		return -ENODEV;
+
+	ir->clk = devm_clk_get(dev, "clk");
+	if (IS_ERR(ir->clk)) {
+		dev_err(dev, "failed to get a ir clock.\n");
+		return PTR_ERR(ir->clk);
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	ir->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ir->base)) {
+		dev_err(dev, "failed to map registers\n");
+		return PTR_ERR(ir->base);
+	}
+
+	ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
+	if (!ir->rc) {
+		dev_err(dev, "failed to allocate device\n");
+		return -ENOMEM;
+	}
+
+	ir->rc->priv = ir;
+	ir->rc->input_name = MTK_IR_DEV;
+	ir->rc->input_phys = MTK_IR_DEV "/input0";
+	ir->rc->input_id.bustype = BUS_HOST;
+	ir->rc->input_id.vendor = 0x0001;
+	ir->rc->input_id.product = 0x0001;
+	ir->rc->input_id.version = 0x0001;
+	map_name = of_get_property(dn, "linux,rc-map-name", NULL);
+	ir->rc->map_name = map_name ?: RC_MAP_EMPTY;
+	ir->rc->dev.parent = dev;
+	ir->rc->driver_name = MTK_IR_DEV;
+	ir->rc->allowed_protocols = RC_BIT_ALL;
+	ir->rc->rx_resolution = MTK_IR_SAMPLE;
+	ir->rc->timeout = MTK_MAX_SAMPLES * (MTK_IR_SAMPLE + 1);
+
+	ret = devm_rc_register_device(dev, ir->rc);
+	if (ret) {
+		dev_err(dev, "failed to register rc device\n");
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, ir);
+
+	ir->irq = platform_get_irq(pdev, 0);
+	if (ir->irq < 0) {
+		dev_err(dev, "no irq resource\n");
+		return -ENODEV;
+	}
+
+	/* Enable interrupt after proper hardware
+	 * setup and IRQ handler registration
+	 */
+	if (clk_prepare_enable(ir->clk)) {
+		dev_err(dev, "try to enable ir_clk failed\n");
+		ret = -EINVAL;
+		goto exit_clkdisable_clk;
+	}
+
+	mtk_irq_disable(ir, MTK_IRINT_EN);
+
+	ret = devm_request_irq(dev, ir->irq, mtk_ir_irq, 0, MTK_IR_DEV, ir);
+	if (ret) {
+		dev_err(dev, "failed request irq\n");
+		goto exit_clkdisable_clk;
+	}
+
+	/* Enable IR and PWM */
+	val = mtk_r32(ir, MTK_CONFIG_HIGH_REG);
+	val |= MTK_PWM_EN | MTK_IR_EN;
+	mtk_w32(ir, val, MTK_CONFIG_HIGH_REG);
+
+	/* Setting sample period */
+	mtk_w32_mask(ir, MTK_CHK_PERIOD, MTK_CHK_PERIOD_MASK,
+		     MTK_CONFIG_LOW_REG);
+
+	mtk_irq_enable(ir, MTK_IRINT_EN);
+
+	dev_info(dev, "Initialized MT7623 IR driver, sample period = %luus\n",
+		 DIV_ROUND_CLOSEST(MTK_IR_SAMPLE, 1000));
+
+	return 0;
+
+exit_clkdisable_clk:
+	clk_disable_unprepare(ir->clk);
+
+	return ret;
+}
+
+static int mtk_ir_remove(struct platform_device *pdev)
+{
+	struct mtk_ir *ir = platform_get_drvdata(pdev);
+
+	/* Avoid contention between remove handler and
+	 * IRQ handler so that disabling IR interrupt and
+	 * waiting for pending IRQ handler to complete
+	 */
+	mtk_irq_disable(ir, MTK_IRINT_EN);
+	synchronize_irq(ir->irq);
+
+	clk_disable_unprepare(ir->clk);
+
+	rc_unregister_device(ir->rc);
+
+	return 0;
+}
+
+static const struct of_device_id mtk_ir_match[] = {
+	{ .compatible = "mediatek,mt7623-cir" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mtk_ir_match);
+
+static struct platform_driver mtk_ir_driver = {
+	.probe          = mtk_ir_probe,
+	.remove         = mtk_ir_remove,
+	.driver = {
+		.name = MTK_IR_DEV,
+		.of_match_table = mtk_ir_match,
+	},
+};
+
+module_platform_driver(mtk_ir_driver);
+
+MODULE_DESCRIPTION("Mediatek IR Receiver Controller Driver");
+MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>");
+MODULE_LICENSE("GPL");
-- 
2.7.4

Re: [PATCH v2 2/2] media: rc: add driver for IR remote receiver on MT7623 SoC

[Sean Young]

Hi Sean

Some more review comments. 

On Tue, Jan 10, 2017 at 05:13:51PM +0800, sean.wang@mediatek.com wrote:
> From: Sean Wang <sean.wang@mediatek.com>
> 
> This patch adds driver for IR controller on MT7623 SoC.
> and should also work on similar Mediatek SoC. Currently
> testing successfully on NEC and SONY remote controller
> only but it should work on others (lirc, rc-5 and rc-6).
> 
> Signed-off-by: Sean Wang <sean.wang@mediatek.com>
> Reviewed-by: Sean Young <sean@mess.org>
> ---
>  drivers/media/rc/Kconfig   |  11 ++
>  drivers/media/rc/Makefile  |   1 +
>  drivers/media/rc/mtk-cir.c | 326 +++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 338 insertions(+)
>  create mode 100644 drivers/media/rc/mtk-cir.c
> 
> diff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig
> index 629e8ca..9228479 100644
> --- a/drivers/media/rc/Kconfig
> +++ b/drivers/media/rc/Kconfig
> @@ -235,6 +235,17 @@ config IR_MESON
>  	   To compile this driver as a module, choose M here: the
>  	   module will be called meson-ir.
>  
> +config IR_MTK
> +	tristate "Mediatek IR remote receiver"
> +	depends on RC_CORE
> +	depends on ARCH_MEDIATEK || COMPILE_TEST
> +	---help---
> +	   Say Y if you want to use the IR remote receiver available
> +	   on Mediatek SoCs.
> +
> +	   To compile this driver as a module, choose M here: the
> +	   module will be called mtk-cir.
> +
>  config IR_NUVOTON
>  	tristate "Nuvoton w836x7hg Consumer Infrared Transceiver"
>  	depends on PNP
> diff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile
> index 3a984ee..a78570b 100644
> --- a/drivers/media/rc/Makefile
> +++ b/drivers/media/rc/Makefile
> @@ -38,3 +38,4 @@ obj-$(CONFIG_RC_ST) += st_rc.o
>  obj-$(CONFIG_IR_SUNXI) += sunxi-cir.o
>  obj-$(CONFIG_IR_IMG) += img-ir/
>  obj-$(CONFIG_IR_SERIAL) += serial_ir.o
> +obj-$(CONFIG_IR_MTK) += mtk-cir.o
> diff --git a/drivers/media/rc/mtk-cir.c b/drivers/media/rc/mtk-cir.c
> new file mode 100644
> index 0000000..f752f63
> --- /dev/null
> +++ b/drivers/media/rc/mtk-cir.c
> @@ -0,0 +1,326 @@
> +/*
> + * Driver for Mediatek IR Receiver Controller
> + *
> + * Copyright (C) 2017 Sean Wang <sean.wang@mediatek.com>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/of_platform.h>
> +#include <linux/reset.h>
> +#include <media/rc-core.h>
> +
> +#define MTK_IR_DEV KBUILD_MODNAME

You could remove this #define and just use KBUILD_MODNAME 
> +
> +/* Register to enable PWM and IR */
> +#define MTK_CONFIG_HIGH_REG       0x0c
> +/* Enable IR pulse width detection */
> +#define MTK_PWM_EN		  BIT(13)
> +/* Enable IR hardware function */
> +#define MTK_IR_EN		  BIT(0)
> +
> +/* Register to setting sample period */
> +#define MTK_CONFIG_LOW_REG        0x10
> +/* Field to set sample period */
> +#define CHK_PERIOD		  DIV_ROUND_CLOSEST(MTK_IR_SAMPLE,  \
> +						    MTK_IR_CLK_PERIOD)
> +#define MTK_CHK_PERIOD            (((CHK_PERIOD) << 8) & (GENMASK(20, 8)))
> +#define MTK_CHK_PERIOD_MASK	  (GENMASK(20, 8))
> +
> +/* Register to clear state of state machine */
> +#define MTK_IRCLR_REG             0x20
> +/* Bit to restart IR receiving */
> +#define MTK_IRCLR		  BIT(0)
> +
> +/* Register containing pulse width data */
> +#define MTK_CHKDATA_REG(i)        (0x88 + 4 * (i))
> +#define MTK_WIDTH_MASK		  (GENMASK(7, 0))
> +
> +/* Register to enable IR interrupt */
> +#define MTK_IRINT_EN_REG          0xcc
> +/* Bit to enable interrupt */
> +#define MTK_IRINT_EN		  BIT(0)
> +
> +/* Register to ack IR interrupt */
> +#define MTK_IRINT_CLR_REG         0xd0
> +/* Bit to clear interrupt status */
> +#define MTK_IRINT_CLR		  BIT(0)
> +
> +/* Maximum count of samples */
> +#define MTK_MAX_SAMPLES		  0xff
> +/* Indicate the end of IR message */
> +#define MTK_IR_END(v, p)	  ((v) == MTK_MAX_SAMPLES && (p) == 0)
> +/* Number of registers to record the pulse width */
> +#define MTK_CHKDATA_SZ		  17
> +/* Source clock frequency */
> +#define MTK_IR_BASE_CLK		  273000000
> +/* Frequency after IR internal divider */
> +#define MTK_IR_CLK_FREQ		  (MTK_IR_BASE_CLK / 4)
> +/* Period for MTK_IR_CLK in ns*/
> +#define MTK_IR_CLK_PERIOD	  DIV_ROUND_CLOSEST(1000000000ul,  \
> +						    MTK_IR_CLK_FREQ)
> +/* Sample period in ns */
> +#define MTK_IR_SAMPLE		  (MTK_IR_CLK_PERIOD * 0xc00)
> +
> +/* struct mtk_ir -	This is the main datasructure for holding the state
> + *			of the driver
> + * @dev:		The device pointer
> + * @rc:			The rc instrance
> + * @irq:		The IRQ that we are using
> + * @base:		The mapped register i/o base
> + * @clk:		The clock that we are using
> + */
> +struct mtk_ir {
> +	struct device	*dev;
> +	struct rc_dev	*rc;
> +	void __iomem	*base;
> +	int		irq;
> +	struct clk	*clk;
> +};
> +
> +static void mtk_w32_mask(struct mtk_ir *ir, u32 val, u32 mask, unsigned int reg)
> +{
> +	u32 tmp;
> +
> +	tmp = __raw_readl(ir->base + reg);
> +	tmp = (tmp & ~mask) | val;
> +	__raw_writel(tmp, ir->base + reg);
> +}
> +
> +static void mtk_w32(struct mtk_ir *ir, u32 val, unsigned int reg)
> +{
> +	__raw_writel(val, ir->base + reg);
> +}
> +
> +static u32 mtk_r32(struct mtk_ir *ir, unsigned int reg)
> +{
> +	return __raw_readl(ir->base + reg);
> +}
> +
> +static inline void mtk_irq_disable(struct mtk_ir *ir, u32 mask)
> +{
> +	u32 val;
> +
> +	val = mtk_r32(ir, MTK_IRINT_EN_REG);
> +	mtk_w32(ir, val & ~mask, MTK_IRINT_EN_REG);
> +}
> +
> +static inline void mtk_irq_enable(struct mtk_ir *ir, u32 mask)
> +{
> +	u32 val;
> +
> +	val = mtk_r32(ir, MTK_IRINT_EN_REG);
> +	mtk_w32(ir, val | mask, MTK_IRINT_EN_REG);
> +}
> +
> +static irqreturn_t mtk_ir_irq(int irqno, void *dev_id)
> +{
> +	struct mtk_ir *ir = dev_id;
> +	u8  wid = 0;
> +	u32 i, j, val;
> +	DEFINE_IR_RAW_EVENT(rawir);
> +
> +	mtk_irq_disable(ir, MTK_IRINT_EN);

The kernel guarantees that calls to the interrupt handler are serialised,
no need to disable the interrupt in the handler.

> +
> +	/* Reset decoder state machine */
> +	ir_raw_event_reset(ir->rc);

Not needed.

> +
> +	/* First message must be pulse */
> +	rawir.pulse = false;

pulse = true?

> +
> +	/* Handle all pulse and space IR controller captures */
> +	for (i = 0 ; i < MTK_CHKDATA_SZ ; i++) {
> +		val = mtk_r32(ir, MTK_CHKDATA_REG(i));
> +		dev_dbg(ir->dev, "@reg%d=0x%08x\n", i, val);
> +
> +		for (j = 0 ; j < 4 ; j++) {
> +			wid = (val & (MTK_WIDTH_MASK << j * 8)) >> j * 8;
> +			rawir.pulse = !rawir.pulse;
> +			rawir.duration = wid * (MTK_IR_SAMPLE + 1);
> +			ir_raw_event_store_with_filter(ir->rc, &rawir);
> +		}

In v1 you would break out of the loop if the ir message was shorter, but
now you are always passing on 68 pulses and spaces. Is that right?

> +	}
> +
> +	/* The maximum number of edges the IR controller can
> +	 * hold is MTK_CHKDATA_SZ * 4. So if received IR messages
> +	 * is over the limit, the last incomplete IR message would
> +	 * be appended trailing space and still would be sent into
> +	 * ir-rc-raw to decode. That helps it is possible that it
> +	 * has enough information to decode a scancode even if the
> +	 * trailing end of the message is missing.
> +	 */
> +	if (!MTK_IR_END(wid, rawir.pulse)) {
> +		rawir.pulse = false;
> +		rawir.duration = MTK_MAX_SAMPLES * (MTK_IR_SAMPLE + 1);
> +		ir_raw_event_store_with_filter(ir->rc, &rawir);
> +	}
> +
> +	ir_raw_event_handle(ir->rc);
> +
> +	/* Restart controller for the next receive */
> +	mtk_w32_mask(ir, 0x1, MTK_IRCLR, MTK_IRCLR_REG);
> +
> +	/* Clear interrupt status */
> +	mtk_w32_mask(ir, 0x1, MTK_IRINT_CLR, MTK_IRINT_CLR_REG);
> +
> +	/* Enable interrupt */
> +	mtk_irq_enable(ir, MTK_IRINT_EN);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int mtk_ir_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct device_node *dn = dev->of_node;
> +	struct resource *res;
> +	struct mtk_ir *ir;
> +	u32 val;
> +	int ret = 0;
> +	const char *map_name;
> +
> +	ir = devm_kzalloc(dev, sizeof(struct mtk_ir), GFP_KERNEL);
> +	if (!ir)
> +		return -ENOMEM;
> +
> +	ir->dev = dev;
> +
> +	if (!of_device_is_compatible(dn, "mediatek,mt7623-cir"))
> +		return -ENODEV;
> +
> +	ir->clk = devm_clk_get(dev, "clk");
> +	if (IS_ERR(ir->clk)) {
> +		dev_err(dev, "failed to get a ir clock.\n");
> +		return PTR_ERR(ir->clk);
> +	}
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	ir->base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(ir->base)) {
> +		dev_err(dev, "failed to map registers\n");
> +		return PTR_ERR(ir->base);
> +	}
> +
> +	ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
> +	if (!ir->rc) {
> +		dev_err(dev, "failed to allocate device\n");
> +		return -ENOMEM;
> +	}
> +
> +	ir->rc->priv = ir;
> +	ir->rc->input_name = MTK_IR_DEV;
> +	ir->rc->input_phys = MTK_IR_DEV "/input0";
> +	ir->rc->input_id.bustype = BUS_HOST;
> +	ir->rc->input_id.vendor = 0x0001;
> +	ir->rc->input_id.product = 0x0001;
> +	ir->rc->input_id.version = 0x0001;
> +	map_name = of_get_property(dn, "linux,rc-map-name", NULL);
> +	ir->rc->map_name = map_name ?: RC_MAP_EMPTY;
> +	ir->rc->dev.parent = dev;
> +	ir->rc->driver_name = MTK_IR_DEV;
> +	ir->rc->allowed_protocols = RC_BIT_ALL;
> +	ir->rc->rx_resolution = MTK_IR_SAMPLE;
> +	ir->rc->timeout = MTK_MAX_SAMPLES * (MTK_IR_SAMPLE + 1);
> +
> +	ret = devm_rc_register_device(dev, ir->rc);

Here you do devm_rc_register_device()

> +	if (ret) {
> +		dev_err(dev, "failed to register rc device\n");
> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, ir);
> +
> +	ir->irq = platform_get_irq(pdev, 0);
> +	if (ir->irq < 0) {
> +		dev_err(dev, "no irq resource\n");
> +		return -ENODEV;
> +	}
> +
> +	/* Enable interrupt after proper hardware
> +	 * setup and IRQ handler registration
> +	 */
> +	if (clk_prepare_enable(ir->clk)) {
> +		dev_err(dev, "try to enable ir_clk failed\n");
> +		ret = -EINVAL;
> +		goto exit_clkdisable_clk;
> +	}
> +
> +	mtk_irq_disable(ir, MTK_IRINT_EN);
> +
> +	ret = devm_request_irq(dev, ir->irq, mtk_ir_irq, 0, MTK_IR_DEV, ir);
> +	if (ret) {
> +		dev_err(dev, "failed request irq\n");
> +		goto exit_clkdisable_clk;
> +	}
> +
> +	/* Enable IR and PWM */
> +	val = mtk_r32(ir, MTK_CONFIG_HIGH_REG);
> +	val |= MTK_PWM_EN | MTK_IR_EN;
> +	mtk_w32(ir, val, MTK_CONFIG_HIGH_REG);
> +
> +	/* Setting sample period */
> +	mtk_w32_mask(ir, MTK_CHK_PERIOD, MTK_CHK_PERIOD_MASK,
> +		     MTK_CONFIG_LOW_REG);
> +
> +	mtk_irq_enable(ir, MTK_IRINT_EN);
> +
> +	dev_info(dev, "Initialized MT7623 IR driver, sample period = %luus\n",
> +		 DIV_ROUND_CLOSEST(MTK_IR_SAMPLE, 1000));
> +
> +	return 0;
> +
> +exit_clkdisable_clk:
> +	clk_disable_unprepare(ir->clk);
> +
> +	return ret;
> +}
> +
> +static int mtk_ir_remove(struct platform_device *pdev)
> +{
> +	struct mtk_ir *ir = platform_get_drvdata(pdev);
> +
> +	/* Avoid contention between remove handler and
> +	 * IRQ handler so that disabling IR interrupt and
> +	 * waiting for pending IRQ handler to complete
> +	 */
> +	mtk_irq_disable(ir, MTK_IRINT_EN);
> +	synchronize_irq(ir->irq);
> +
> +	clk_disable_unprepare(ir->clk);
> +
> +	rc_unregister_device(ir->rc);

Yet here you explicitly call rc_unregister_device(). Since it was registered
with the devm call, this call is not needed and will lead to double frees etc

> +
> +	return 0;
> +}
> +
> +static const struct of_device_id mtk_ir_match[] = {
> +	{ .compatible = "mediatek,mt7623-cir" },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, mtk_ir_match);
> +
> +static struct platform_driver mtk_ir_driver = {
> +	.probe          = mtk_ir_probe,
> +	.remove         = mtk_ir_remove,
> +	.driver = {
> +		.name = MTK_IR_DEV,
> +		.of_match_table = mtk_ir_match,
> +	},
> +};
> +
> +module_platform_driver(mtk_ir_driver);
> +
> +MODULE_DESCRIPTION("Mediatek IR Receiver Controller Driver");
> +MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>");
> +MODULE_LICENSE("GPL");
> -- 
> 2.7.4
> 

Re: [PATCH v2 2/2] media: rc: add driver for IR remote receiver on MT7623 SoC

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 2615 bytes --]

Hi Sean,

[auto build test ERROR on linuxtv-media/master]
[also build test ERROR on v4.10-rc3 next-20170110]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/sean-wang-mediatek-com/Documentation-devicetree-Add-document-bindings-for-mtk-cir/20170110-193357
base:   git://linuxtv.org/media_tree.git master
config: x86_64-allmodconfig (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All errors (new ones prefixed by >>):

   include/linux/compiler.h:253:8: sparse: attribute 'no_sanitize_address': unknown attribute
   drivers/media/rc/mtk-cir.c:215:41: sparse: too many arguments for function devm_rc_allocate_device
   drivers/media/rc/mtk-cir.c: In function 'mtk_ir_probe':
>> drivers/media/rc/mtk-cir.c:215:11: error: too many arguments to function 'devm_rc_allocate_device'
     ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
              ^~~~~~~~~~~~~~~~~~~~~~~
   In file included from drivers/media/rc/mtk-cir.c:22:0:
   include/media/rc-core.h:213:16: note: declared here
    struct rc_dev *devm_rc_allocate_device(struct device *dev);
                   ^~~~~~~~~~~~~~~~~~~~~~~

sparse warnings: (new ones prefixed by >>)

   include/linux/compiler.h:253:8: sparse: attribute 'no_sanitize_address': unknown attribute
>> drivers/media/rc/mtk-cir.c:215:41: sparse: too many arguments for function devm_rc_allocate_device
   drivers/media/rc/mtk-cir.c: In function 'mtk_ir_probe':
   drivers/media/rc/mtk-cir.c:215:11: error: too many arguments to function 'devm_rc_allocate_device'
     ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
              ^~~~~~~~~~~~~~~~~~~~~~~
   In file included from drivers/media/rc/mtk-cir.c:22:0:
   include/media/rc-core.h:213:16: note: declared here
    struct rc_dev *devm_rc_allocate_device(struct device *dev);
                   ^~~~~~~~~~~~~~~~~~~~~~~

vim +/devm_rc_allocate_device +215 drivers/media/rc/mtk-cir.c

   209		ir->base = devm_ioremap_resource(dev, res);
   210		if (IS_ERR(ir->base)) {
   211			dev_err(dev, "failed to map registers\n");
   212			return PTR_ERR(ir->base);
   213		}
   214	
 > 215		ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
   216		if (!ir->rc) {
   217			dev_err(dev, "failed to allocate device\n");
   218			return -ENOMEM;

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 57747 bytes --]

Re: [PATCH v2 2/2] media: rc: add driver for IR remote receiver on MT7623 SoC

[Sean Wang]

On Tue, 2017-01-10 at 11:09 +0000, Sean Young wrote:

> > +#include <linux/clk.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/module.h>
> > +#include <linux/of_platform.h>
> > +#include <linux/reset.h>
> > +#include <media/rc-core.h>
> > +
> > +#define MTK_IR_DEV KBUILD_MODNAME
> 
> You could remove this #define and just use KBUILD_MODNAME

I preferred to use MTK_IR_DEV internally that helps
renaming in the future if necessary.
>  
> > +
> > +/* Register to enable PWM and IR */
> > +#define MTK_CONFIG_HIGH_REG       0x0c
> > +/* Enable IR pulse width detection */
> > +#define MTK_PWM_EN		  BIT(13)
> > +/* Enable IR hardware function */
> > +#define MTK_IR_EN		  BIT(0)
> > +
> > +/* Register to setting sample period */
> > +#define MTK_CONFIG_LOW_REG        0x10
> > +/* Field to set sample period */
> > +#define CHK_PERIOD		  DIV_ROUND_CLOSEST(MTK_IR_SAMPLE,  \
> > +						    MTK_IR_CLK_PERIOD)
> > +#define MTK_CHK_PERIOD            (((CHK_PERIOD) << 8) & (GENMASK(20, 8)))
> > +#define MTK_CHK_PERIOD_MASK	  (GENMASK(20, 8))
> > +
> > +/* Register to clear state of state machine */
> > +#define MTK_IRCLR_REG             0x20
> > +/* Bit to restart IR receiving */
> > +#define MTK_IRCLR		  BIT(0)
> > +
> > +/* Register containing pulse width data */
> > +#define MTK_CHKDATA_REG(i)        (0x88 + 4 * (i))
> > +#define MTK_WIDTH_MASK		  (GENMASK(7, 0))
> > +
> > +/* Register to enable IR interrupt */
> > +#define MTK_IRINT_EN_REG          0xcc
> > +/* Bit to enable interrupt */
> > +#define MTK_IRINT_EN		  BIT(0)
> > +
> > +/* Register to ack IR interrupt */
> > +#define MTK_IRINT_CLR_REG         0xd0
> > +/* Bit to clear interrupt status */
> > +#define MTK_IRINT_CLR		  BIT(0)
> > +
> > +/* Maximum count of samples */
> > +#define MTK_MAX_SAMPLES		  0xff
> > +/* Indicate the end of IR message */
> > +#define MTK_IR_END(v, p)	  ((v) == MTK_MAX_SAMPLES && (p) == 0)
> > +/* Number of registers to record the pulse width */
> > +#define MTK_CHKDATA_SZ		  17
> > +/* Source clock frequency */
> > +#define MTK_IR_BASE_CLK		  273000000
> > +/* Frequency after IR internal divider */
> > +#define MTK_IR_CLK_FREQ		  (MTK_IR_BASE_CLK / 4)

> > +static irqreturn_t mtk_ir_irq(int irqno, void *dev_id)
> > +{
> > +	struct mtk_ir *ir = dev_id;
> > +	u8  wid = 0;
> > +	u32 i, j, val;
> > +	DEFINE_IR_RAW_EVENT(rawir);
> > +
> > +	mtk_irq_disable(ir, MTK_IRINT_EN);
> 
> The kernel guarantees that calls to the interrupt handler are serialised,
> no need to disable the interrupt in the handler.

agreed. I will save the mtk irq disable/enable and retest again.


> > +
> > +	/* Reset decoder state machine */
> > +	ir_raw_event_reset(ir->rc);
> 
> Not needed.


two reasons I added the line here

1) 
I thought it is possible the decoder goes to the
middle state when getting the data not belonged
to the protocol. If so, that would cause the decoding
fails in the next time receiving the valid protocol data.

2) 
the mtk hardware register always contains the start of 
IR message. So force to sync the state between 
HW and ir-core.



> > +
> > +	/* First message must be pulse */
> > +	rawir.pulse = false;
> 
> pulse = true?

becasue of rawir.pulse = !rawir.pulse does as below
so the initial value is set as false.

> > +
> > +	/* Handle all pulse and space IR controller captures */
> > +	for (i = 0 ; i < MTK_CHKDATA_SZ ; i++) {
> > +		val = mtk_r32(ir, MTK_CHKDATA_REG(i));
> > +		dev_dbg(ir->dev, "@reg%d=0x%08x\n", i, val);
> > +
> > +		for (j = 0 ; j < 4 ; j++) {
> > +			wid = (val & (MTK_WIDTH_MASK << j * 8)) >> j * 8;
> > +			rawir.pulse = !rawir.pulse;
> > +			rawir.duration = wid * (MTK_IR_SAMPLE + 1);
> > +			ir_raw_event_store_with_filter(ir->rc, &rawir);
> > +		}
> 
> In v1 you would break out of the loop if the ir message was shorter, but
> now you are always passing on 68 pulses and spaces. Is that right?

as I asked in the previous mail list as below i copied from it, so i
made some changes ...

"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
> I had another question. I found multiple and same IR messages being
> received when using SONY remote controller. Should driver needs to
> report each message or only one of these to the upper layer ?

In general the driver shouldn't try to change any IR message, this
should be done in rc-core if necessary.

rc-core should handle this correctly. If the same key is received twice
within IR_KEYPRESS_TIMEOUT (250ms) then it not reported to the input
layer.
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""

for example:
the 68 pulse/spaces might contains 2.x IR messages when I
pressed one key on SONY remote control. 

the v1 proposed is passing only one IR message into ir-core ; 
the v2 done is passing all IR messages even including the last
incomplete message into ir-core. 

But I was still afraid the state machine can't  go back to initial state
after receiving these incomplete data. 

So the ir_raw_event_reset() call in the beginning of ISR seems becoming
more important.

> > +	}
> > +
> > +	/* The maximum number of edges the IR controller can
> > +	 * hold is MTK_CHKDATA_SZ * 4. So if received IR messages
> > +	 * is over the limit, the last incomplete IR message would
> > +	 * be appended trailing space and still would be sent into
> > +	 * ir-rc-raw to decode. That helps it is possible that it
> > +	 * has enough information to decode a scancode even if the
> > +	 * trailing end of the message is missing.
> > +	 */
> > +	if (!MTK_IR_END(wid, rawir.pulse)) {
> > +		rawir.pulse = false;
> > +		rawir.duration = MTK_MAX_SAMPLES * (MTK_IR_SAMPLE + 1);
> > +		ir_raw_event_store_with_filter(ir->rc, &rawir);
> > +	}
> > +
> > +	ir_raw_event_handle(ir->rc);
> > +
> > +	/* Restart controller for the next receive */
> > +	mtk_w32_mask(ir, 0x1, MTK_IRCLR, MTK_IRCLR_REG);
> > +
> > +	/* Clear interrupt status */
> > +	mtk_w32_mask(ir, 0x1, MTK_IRINT_CLR, MTK_IRINT_CLR_REG);
> > +
> > +	/* Enable interrupt */
> > +	mtk_irq_enable(ir, MTK_IRINT_EN);
> > +
> > +	return IRQ_HANDLED;
> > +}
> > +
> > +static int mtk_ir_probe(struct platform_device *pdev)
> > +{
> > +	struct device *dev = &pdev->dev;
> > +	struct device_node *dn = dev->of_node;
> > +	struct resource *res;
> > +	struct mtk_ir *ir;
> > +	u32 val;
> > +	int ret = 0;
> > +	const char *map_name;
> > +
> > +	ir = devm_kzalloc(dev, sizeof(struct mtk_ir), GFP_KERNEL);
> > +	if (!ir)
> > +		return -ENOMEM;
> > +
> > +	ir->dev = dev;
> > +
> > +	if (!of_device_is_compatible(dn, "mediatek,mt7623-cir"))
> > +		return -ENODEV;
> > +
> > +	ir->clk = devm_clk_get(dev, "clk");
> > +	if (IS_ERR(ir->clk)) {
> > +		dev_err(dev, "failed to get a ir clock.\n");
> > +		return PTR_ERR(ir->clk);
> > +	}
> > +
> > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	ir->base = devm_ioremap_resource(dev, res);
> > +	if (IS_ERR(ir->base)) {
> > +		dev_err(dev, "failed to map registers\n");
> > +		return PTR_ERR(ir->base);
> > +	}
> > +
> > +	ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
> > +	if (!ir->rc) {
> > +		dev_err(dev, "failed to allocate device\n");
> > +		return -ENOMEM;
> > +	}
> > +
> > +	ir->rc->priv = ir;
> > +	ir->rc->input_name = MTK_IR_DEV;
> > +	ir->rc->input_phys = MTK_IR_DEV "/input0";
> > +	ir->rc->input_id.bustype = BUS_HOST;
> > +	ir->rc->input_id.vendor = 0x0001;
> > +	ir->rc->input_id.product = 0x0001;
> > +	ir->rc->input_id.version = 0x0001;
> > +	map_name = of_get_property(dn, "linux,rc-map-name", NULL);
> > +	ir->rc->map_name = map_name ?: RC_MAP_EMPTY;
> > +	ir->rc->dev.parent = dev;
> > +	ir->rc->driver_name = MTK_IR_DEV;
> > +	ir->rc->allowed_protocols = RC_BIT_ALL;
> > +	ir->rc->rx_resolution = MTK_IR_SAMPLE;
> > +	ir->rc->timeout = MTK_MAX_SAMPLES * (MTK_IR_SAMPLE + 1);
> > +
> > +	ret = devm_rc_register_device(dev, ir->rc);
> 
> Here you do devm_rc_register_device()

does it have problem ?


> > +	if (ret) {
> > +		dev_err(dev, "failed to register rc device\n");
> > +		return ret;
> > +	}
> > +
> > +	platform_set_drvdata(pdev, ir);
> > +
> > +	ir->irq = platform_get_irq(pdev, 0);
> > +	if (ir->irq < 0) {
> > +		dev_err(dev, "no irq resource\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	/* Enable interrupt after proper hardware
> > +	 * setup and IRQ handler registration
> > +	 */
> > +	if (clk_prepare_enable(ir->clk)) {
> > +		dev_err(dev, "try to enable ir_clk failed\n");
> > +		ret = -EINVAL;
> > +		goto exit_clkdisable_clk;
> > +	}
> > +
> > +	mtk_irq_disable(ir, MTK_IRINT_EN);
> > +
> > +	ret = devm_request_irq(dev, ir->irq, mtk_ir_irq, 0, MTK_IR_DEV, ir);
> > +	if (ret) {
> > +		dev_err(dev, "failed request irq\n");
> > +		goto exit_clkdisable_clk;
> > +	}
> > +
> > +	/* Enable IR and PWM */
> > +	val = mtk_r32(ir, MTK_CONFIG_HIGH_REG);
> > +	val |= MTK_PWM_EN | MTK_IR_EN;
> > +	mtk_w32(ir, val, MTK_CONFIG_HIGH_REG);
> > +
> > +	/* Setting sample period */
> > +	mtk_w32_mask(ir, MTK_CHK_PERIOD, MTK_CHK_PERIOD_MASK,
> > +		     MTK_CONFIG_LOW_REG);
> > +
> > +	mtk_irq_enable(ir, MTK_IRINT_EN);
> > +
> > +	dev_info(dev, "Initialized MT7623 IR driver, sample period = %luus\n",
> > +		 DIV_ROUND_CLOSEST(MTK_IR_SAMPLE, 1000));
> > +
> > +	return 0;
> > +
> > +exit_clkdisable_clk:
> > +	clk_disable_unprepare(ir->clk);
> > +
> > +	return ret;
> > +}
> > +
> > +static int mtk_ir_remove(struct platform_device *pdev)
> > +{
> > +	struct mtk_ir *ir = platform_get_drvdata(pdev);
> > +
> > +	/* Avoid contention between remove handler and
> > +	 * IRQ handler so that disabling IR interrupt and
> > +	 * waiting for pending IRQ handler to complete
> > +	 */
> > +	mtk_irq_disable(ir, MTK_IRINT_EN);
> > +	synchronize_irq(ir->irq);
> > +
> > +	clk_disable_unprepare(ir->clk);
> > +
> > +	rc_unregister_device(ir->rc);
> 
> Yet here you explicitly call rc_unregister_device(). Since it was registered
> with the devm call, this call is not needed and will lead to double frees etc

bug :( .  I will fix it ..

> > +
> > +	return 0;
> > +}
> > +
> > +static const struct of_device_id mtk_ir_match[] = {
> > +	{ .compatible = "mediatek,mt7623-cir" },
> > +	{},
> > +};
> > +MODULE_DEVICE_TABLE(of, mtk_ir_match);
> > +
> > +static struct platform_driver mtk_ir_driver = {
> > +	.probe          = mtk_ir_probe,
> > +	.remove         = mtk_ir_remove,
> > +	.driver = {
> > +		.name = MTK_IR_DEV,
> > +		.of_match_table = mtk_ir_match,
> > +	},
> > +};
> > +
> > +module_platform_driver(mtk_ir_driver);
> > +
> > +MODULE_DESCRIPTION("Mediatek IR Receiver Controller Driver");
> > +MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>");
> > +MODULE_LICENSE("GPL");
> > -- 
> > 2.7.4
> > 

Re: [PATCH v2 2/2] media: rc: add driver for IR remote receiver on MT7623 SoC

[Sean Young]

Hi Sean,

The driver is looking very good, we are looking at minor details now.

On Tue, Jan 10, 2017 at 09:59:49PM +0800, Sean Wang wrote:
> On Tue, 2017-01-10 at 11:09 +0000, Sean Young wrote:
> 
> > > +#include <linux/clk.h>
> > > +#include <linux/interrupt.h>
> > > +#include <linux/module.h>
> > > +#include <linux/of_platform.h>
> > > +#include <linux/reset.h>
> > > +#include <media/rc-core.h>
> > > +
> > > +#define MTK_IR_DEV KBUILD_MODNAME
> > 
> > You could remove this #define and just use KBUILD_MODNAME
> 
> I preferred to use MTK_IR_DEV internally that helps
> renaming in the future if necessary.

ok.

> >  
> > > +
> > > +/* Register to enable PWM and IR */
> > > +#define MTK_CONFIG_HIGH_REG       0x0c
> > > +/* Enable IR pulse width detection */
> > > +#define MTK_PWM_EN		  BIT(13)
> > > +/* Enable IR hardware function */
> > > +#define MTK_IR_EN		  BIT(0)
> > > +
> > > +/* Register to setting sample period */
> > > +#define MTK_CONFIG_LOW_REG        0x10
> > > +/* Field to set sample period */
> > > +#define CHK_PERIOD		  DIV_ROUND_CLOSEST(MTK_IR_SAMPLE,  \
> > > +						    MTK_IR_CLK_PERIOD)
> > > +#define MTK_CHK_PERIOD            (((CHK_PERIOD) << 8) & (GENMASK(20, 8)))
> > > +#define MTK_CHK_PERIOD_MASK	  (GENMASK(20, 8))
> > > +
> > > +/* Register to clear state of state machine */
> > > +#define MTK_IRCLR_REG             0x20
> > > +/* Bit to restart IR receiving */
> > > +#define MTK_IRCLR		  BIT(0)
> > > +
> > > +/* Register containing pulse width data */
> > > +#define MTK_CHKDATA_REG(i)        (0x88 + 4 * (i))
> > > +#define MTK_WIDTH_MASK		  (GENMASK(7, 0))
> > > +
> > > +/* Register to enable IR interrupt */
> > > +#define MTK_IRINT_EN_REG          0xcc
> > > +/* Bit to enable interrupt */
> > > +#define MTK_IRINT_EN		  BIT(0)
> > > +
> > > +/* Register to ack IR interrupt */
> > > +#define MTK_IRINT_CLR_REG         0xd0
> > > +/* Bit to clear interrupt status */
> > > +#define MTK_IRINT_CLR		  BIT(0)
> > > +
> > > +/* Maximum count of samples */
> > > +#define MTK_MAX_SAMPLES		  0xff
> > > +/* Indicate the end of IR message */
> > > +#define MTK_IR_END(v, p)	  ((v) == MTK_MAX_SAMPLES && (p) == 0)
> > > +/* Number of registers to record the pulse width */
> > > +#define MTK_CHKDATA_SZ		  17
> > > +/* Source clock frequency */
> > > +#define MTK_IR_BASE_CLK		  273000000
> > > +/* Frequency after IR internal divider */
> > > +#define MTK_IR_CLK_FREQ		  (MTK_IR_BASE_CLK / 4)
> 
> > > +static irqreturn_t mtk_ir_irq(int irqno, void *dev_id)
> > > +{
> > > +	struct mtk_ir *ir = dev_id;
> > > +	u8  wid = 0;
> > > +	u32 i, j, val;
> > > +	DEFINE_IR_RAW_EVENT(rawir);
> > > +
> > > +	mtk_irq_disable(ir, MTK_IRINT_EN);
> > 
> > The kernel guarantees that calls to the interrupt handler are serialised,
> > no need to disable the interrupt in the handler.
> 
> agreed. I will save the mtk irq disable/enable and retest again.
> 
> 
> > > +
> > > +	/* Reset decoder state machine */
> > > +	ir_raw_event_reset(ir->rc);
> > 
> > Not needed.
> 
> 
> two reasons I added the line here
> 
> 1) 
> I thought it is possible the decoder goes to the
> middle state when getting the data not belonged
> to the protocol. If so, that would cause the decoding
> fails in the next time receiving the valid protocol data.

The last IR event submitted will always be a long space, that's enough
to reset the decoders. Adding a ir_raw_event_reset() will do this
more explicitly, rather than their state machines resetting themselves
through the trailing space.

> 2) 
> the mtk hardware register always contains the start of 
> IR message. So force to sync the state between 
> HW and ir-core.
> 
> 
> 
> > > +
> > > +	/* First message must be pulse */
> > > +	rawir.pulse = false;
> > 
> > pulse = true?
> 
> becasue of rawir.pulse = !rawir.pulse does as below
> so the initial value is set as false.

Ah, sorry, of course. :)

> > > +
> > > +	/* Handle all pulse and space IR controller captures */
> > > +	for (i = 0 ; i < MTK_CHKDATA_SZ ; i++) {
> > > +		val = mtk_r32(ir, MTK_CHKDATA_REG(i));
> > > +		dev_dbg(ir->dev, "@reg%d=0x%08x\n", i, val);
> > > +
> > > +		for (j = 0 ; j < 4 ; j++) {
> > > +			wid = (val & (MTK_WIDTH_MASK << j * 8)) >> j * 8;
> > > +			rawir.pulse = !rawir.pulse;
> > > +			rawir.duration = wid * (MTK_IR_SAMPLE + 1);
> > > +			ir_raw_event_store_with_filter(ir->rc, &rawir);
> > > +		}
> > 
> > In v1 you would break out of the loop if the ir message was shorter, but
> > now you are always passing on 68 pulses and spaces. Is that right?
> 
> as I asked in the previous mail list as below i copied from it, so i
> made some changes ...
> 
> """""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
> > I had another question. I found multiple and same IR messages being
> > received when using SONY remote controller. Should driver needs to
> > report each message or only one of these to the upper layer ?
> 
> In general the driver shouldn't try to change any IR message, this
> should be done in rc-core if necessary.
> 
> rc-core should handle this correctly. If the same key is received twice
> within IR_KEYPRESS_TIMEOUT (250ms) then it not reported to the input
> layer.
> """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
> 
> for example:
> the 68 pulse/spaces might contains 2.x IR messages when I
> pressed one key on SONY remote control. 
> 
> the v1 proposed is passing only one IR message into ir-core ; 
> the v2 done is passing all IR messages even including the last
> incomplete message into ir-core. 

Yes, agreed. Sorry if I wasn't clear. I just wanted to make sure you've
thought about what happens when the IR message is short (e.g. rc-5 with
23 pulse-spaces). Are the remaining registers 0 or do we get stale data
from a previous transmit?

> But I was still afraid the state machine can't  go back to initial state
> after receiving these incomplete data. 
> 
> So the ir_raw_event_reset() call in the beginning of ISR seems becoming
> more important.
> 
> > > +	}
> > > +
> > > +	/* The maximum number of edges the IR controller can
> > > +	 * hold is MTK_CHKDATA_SZ * 4. So if received IR messages
> > > +	 * is over the limit, the last incomplete IR message would
> > > +	 * be appended trailing space and still would be sent into
> > > +	 * ir-rc-raw to decode. That helps it is possible that it
> > > +	 * has enough information to decode a scancode even if the
> > > +	 * trailing end of the message is missing.
> > > +	 */
> > > +	if (!MTK_IR_END(wid, rawir.pulse)) {
> > > +		rawir.pulse = false;
> > > +		rawir.duration = MTK_MAX_SAMPLES * (MTK_IR_SAMPLE + 1);
> > > +		ir_raw_event_store_with_filter(ir->rc, &rawir);
> > > +	}

See here you add a long space if one was not added already.

> > > +
> > > +	ir_raw_event_handle(ir->rc);
> > > +
> > > +	/* Restart controller for the next receive */
> > > +	mtk_w32_mask(ir, 0x1, MTK_IRCLR, MTK_IRCLR_REG);
> > > +
> > > +	/* Clear interrupt status */
> > > +	mtk_w32_mask(ir, 0x1, MTK_IRINT_CLR, MTK_IRINT_CLR_REG);
> > > +
> > > +	/* Enable interrupt */
> > > +	mtk_irq_enable(ir, MTK_IRINT_EN);
> > > +
> > > +	return IRQ_HANDLED;
> > > +}
> > > +
> > > +static int mtk_ir_probe(struct platform_device *pdev)
> > > +{
> > > +	struct device *dev = &pdev->dev;
> > > +	struct device_node *dn = dev->of_node;
> > > +	struct resource *res;
> > > +	struct mtk_ir *ir;
> > > +	u32 val;
> > > +	int ret = 0;
> > > +	const char *map_name;
> > > +
> > > +	ir = devm_kzalloc(dev, sizeof(struct mtk_ir), GFP_KERNEL);
> > > +	if (!ir)
> > > +		return -ENOMEM;
> > > +
> > > +	ir->dev = dev;
> > > +
> > > +	if (!of_device_is_compatible(dn, "mediatek,mt7623-cir"))
> > > +		return -ENODEV;
> > > +
> > > +	ir->clk = devm_clk_get(dev, "clk");
> > > +	if (IS_ERR(ir->clk)) {
> > > +		dev_err(dev, "failed to get a ir clock.\n");
> > > +		return PTR_ERR(ir->clk);
> > > +	}
> > > +
> > > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > +	ir->base = devm_ioremap_resource(dev, res);
> > > +	if (IS_ERR(ir->base)) {
> > > +		dev_err(dev, "failed to map registers\n");
> > > +		return PTR_ERR(ir->base);
> > > +	}
> > > +
> > > +	ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
> > > +	if (!ir->rc) {
> > > +		dev_err(dev, "failed to allocate device\n");
> > > +		return -ENOMEM;
> > > +	}
> > > +
> > > +	ir->rc->priv = ir;
> > > +	ir->rc->input_name = MTK_IR_DEV;
> > > +	ir->rc->input_phys = MTK_IR_DEV "/input0";
> > > +	ir->rc->input_id.bustype = BUS_HOST;
> > > +	ir->rc->input_id.vendor = 0x0001;
> > > +	ir->rc->input_id.product = 0x0001;
> > > +	ir->rc->input_id.version = 0x0001;
> > > +	map_name = of_get_property(dn, "linux,rc-map-name", NULL);
> > > +	ir->rc->map_name = map_name ?: RC_MAP_EMPTY;
> > > +	ir->rc->dev.parent = dev;
> > > +	ir->rc->driver_name = MTK_IR_DEV;
> > > +	ir->rc->allowed_protocols = RC_BIT_ALL;
> > > +	ir->rc->rx_resolution = MTK_IR_SAMPLE;
> > > +	ir->rc->timeout = MTK_MAX_SAMPLES * (MTK_IR_SAMPLE + 1);
> > > +
> > > +	ret = devm_rc_register_device(dev, ir->rc);
> > 
> > Here you do devm_rc_register_device()
> 
> does it have problem ?

Sorry, no. I just wanted to highlight wrt a comment below.
> 
> 
> > > +	if (ret) {
> > > +		dev_err(dev, "failed to register rc device\n");
> > > +		return ret;
> > > +	}
> > > +
> > > +	platform_set_drvdata(pdev, ir);
> > > +
> > > +	ir->irq = platform_get_irq(pdev, 0);
> > > +	if (ir->irq < 0) {
> > > +		dev_err(dev, "no irq resource\n");
> > > +		return -ENODEV;
> > > +	}
> > > +
> > > +	/* Enable interrupt after proper hardware
> > > +	 * setup and IRQ handler registration
> > > +	 */
> > > +	if (clk_prepare_enable(ir->clk)) {
> > > +		dev_err(dev, "try to enable ir_clk failed\n");
> > > +		ret = -EINVAL;
> > > +		goto exit_clkdisable_clk;
> > > +	}
> > > +
> > > +	mtk_irq_disable(ir, MTK_IRINT_EN);
> > > +
> > > +	ret = devm_request_irq(dev, ir->irq, mtk_ir_irq, 0, MTK_IR_DEV, ir);
> > > +	if (ret) {
> > > +		dev_err(dev, "failed request irq\n");
> > > +		goto exit_clkdisable_clk;
> > > +	}
> > > +
> > > +	/* Enable IR and PWM */
> > > +	val = mtk_r32(ir, MTK_CONFIG_HIGH_REG);
> > > +	val |= MTK_PWM_EN | MTK_IR_EN;
> > > +	mtk_w32(ir, val, MTK_CONFIG_HIGH_REG);
> > > +
> > > +	/* Setting sample period */
> > > +	mtk_w32_mask(ir, MTK_CHK_PERIOD, MTK_CHK_PERIOD_MASK,
> > > +		     MTK_CONFIG_LOW_REG);
> > > +
> > > +	mtk_irq_enable(ir, MTK_IRINT_EN);
> > > +
> > > +	dev_info(dev, "Initialized MT7623 IR driver, sample period = %luus\n",
> > > +		 DIV_ROUND_CLOSEST(MTK_IR_SAMPLE, 1000));
> > > +
> > > +	return 0;
> > > +
> > > +exit_clkdisable_clk:
> > > +	clk_disable_unprepare(ir->clk);
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static int mtk_ir_remove(struct platform_device *pdev)
> > > +{
> > > +	struct mtk_ir *ir = platform_get_drvdata(pdev);
> > > +
> > > +	/* Avoid contention between remove handler and
> > > +	 * IRQ handler so that disabling IR interrupt and
> > > +	 * waiting for pending IRQ handler to complete
> > > +	 */
> > > +	mtk_irq_disable(ir, MTK_IRINT_EN);
> > > +	synchronize_irq(ir->irq);
> > > +
> > > +	clk_disable_unprepare(ir->clk);
> > > +
> > > +	rc_unregister_device(ir->rc);
> > 
> > Yet here you explicitly call rc_unregister_device(). Since it was registered
> > with the devm call, this call is not needed and will lead to double frees etc
> 
> bug :( .  I will fix it ..
> 
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static const struct of_device_id mtk_ir_match[] = {
> > > +	{ .compatible = "mediatek,mt7623-cir" },
> > > +	{},
> > > +};
> > > +MODULE_DEVICE_TABLE(of, mtk_ir_match);
> > > +
> > > +static struct platform_driver mtk_ir_driver = {
> > > +	.probe          = mtk_ir_probe,
> > > +	.remove         = mtk_ir_remove,
> > > +	.driver = {
> > > +		.name = MTK_IR_DEV,
> > > +		.of_match_table = mtk_ir_match,
> > > +	},
> > > +};
> > > +
> > > +module_platform_driver(mtk_ir_driver);
> > > +
> > > +MODULE_DESCRIPTION("Mediatek IR Receiver Controller Driver");
> > > +MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>");
> > > +MODULE_LICENSE("GPL");
> > > -- 
> > > 2.7.4
> > > 
> 
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-media" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v2 2/2] media: rc: add driver for IR remote receiver on MT7623 SoC

[Andi Shyti]

Hi Sean,

>    include/linux/compiler.h:253:8: sparse: attribute 'no_sanitize_address': unknown attribute
> >> drivers/media/rc/mtk-cir.c:215:41: sparse: too many arguments for function devm_rc_allocate_device
>    drivers/media/rc/mtk-cir.c: In function 'mtk_ir_probe':
>    drivers/media/rc/mtk-cir.c:215:11: error: too many arguments to function 'devm_rc_allocate_device'
>      ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
>               ^~~~~~~~~~~~~~~~~~~~~~~
>    In file included from drivers/media/rc/mtk-cir.c:22:0:
>    include/media/rc-core.h:213:16: note: declared here
>     struct rc_dev *devm_rc_allocate_device(struct device *dev);
>                    ^~~~~~~~~~~~~~~~~~~~~~~
> 
> vim +/devm_rc_allocate_device +215 drivers/media/rc/mtk-cir.c
> 
>    209		ir->base = devm_ioremap_resource(dev, res);
>    210		if (IS_ERR(ir->base)) {
>    211			dev_err(dev, "failed to map registers\n");
>    212			return PTR_ERR(ir->base);
>    213		}
>    214	
>  > 215		ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);

this error comes because the patches I pointed out have not been
applied yet. I guess you can ignore them as long as you tested
yours on top those patches.

Andi

Re: [PATCH v2 2/2] media: rc: add driver for IR remote receiver on MT7623 SoC

[Sean Wang]

On Tue, 2017-01-10 at 17:23 +0000, Sean Young wrote:
> Hi Sean,
> 

> > > 
> > > The kernel guarantees that calls to the interrupt handler are serialised,
> > > no need to disable the interrupt in the handler.
> > 
> > agreed. I will save the mtk irq disable/enable and retest again.
> > 
> > 
> > > > +
> > > > +	/* Reset decoder state machine */
> > > > +	ir_raw_event_reset(ir->rc);
> > > 
> > > Not needed.
> > 
> > 
> > two reasons I added the line here
> > 
> > 1) 
> > I thought it is possible the decoder goes to the
> > middle state when getting the data not belonged
> > to the protocol. If so, that would cause the decoding
> > fails in the next time receiving the valid protocol data.
> 
> The last IR event submitted will always be a long space, that's enough
> to reset the decoders. Adding a ir_raw_event_reset() will do this
> more explicitly, rather than their state machines resetting themselves
> through the trailing space.

thanks for the detailed explanation :) i got it

but some hardware limitation let me can't do it in implicit way :(

reset decoder state machine explicitly is needed because 
1) the longest duration for space MTK IR hardware can record is not
safely long. e.g  12ms if rx resolution is 46us by default. There is
still the risk to satisfying every decoder to reset themselves through
long enough trailing spaces
 
2) the IRQ handler called guarantees that start of IR message is always
contained in and starting from register MTK_CHKDATA_REG(0). 

I will add these words for hardware limitation into comments in the
driver

> > 2) 
> > the mtk hardware register always contains the start of 
> > IR message. So force to sync the state between 
> > HW and ir-core.
> > 
> > 
> > 
> > > > +
> > > > +	/* First message must be pulse */
> > > > +	rawir.pulse = false;
> > > 
> > > pulse = true?
> > 
> > becasue of rawir.pulse = !rawir.pulse does as below
> > so the initial value is set as false.
> 
> Ah, sorry, of course. :)
> 
> > > > +
> > > > +	/* Handle all pulse and space IR controller captures */
> > > > +	for (i = 0 ; i < MTK_CHKDATA_SZ ; i++) {
> > > > +		val = mtk_r32(ir, MTK_CHKDATA_REG(i));
> > > > +		dev_dbg(ir->dev, "@reg%d=0x%08x\n", i, val);
> > > > +
> > > > +		for (j = 0 ; j < 4 ; j++) {
> > > > +			wid = (val & (MTK_WIDTH_MASK << j * 8)) >> j * 8;
> > > > +			rawir.pulse = !rawir.pulse;
> > > > +			rawir.duration = wid * (MTK_IR_SAMPLE + 1);
> > > > +			ir_raw_event_store_with_filter(ir->rc, &rawir);
> > > > +		}
> > > 
> > > In v1 you would break out of the loop if the ir message was shorter, but
> > > now you are always passing on 68 pulses and spaces. Is that right?
> > 
> > as I asked in the previous mail list as below i copied from it, so i
> > made some changes ...
> > 
> > """""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
> > > I had another question. I found multiple and same IR messages being
> > > received when using SONY remote controller. Should driver needs to
> > > report each message or only one of these to the upper layer ?
> > 
> > In general the driver shouldn't try to change any IR message, this
> > should be done in rc-core if necessary.
> > 
> > rc-core should handle this correctly. If the same key is received twice
> > within IR_KEYPRESS_TIMEOUT (250ms) then it not reported to the input
> > layer.
> > """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
> > 
> > for example:
> > the 68 pulse/spaces might contains 2.x IR messages when I
> > pressed one key on SONY remote control. 
> > 
> > the v1 proposed is passing only one IR message into ir-core ; 
> > the v2 done is passing all IR messages even including the last
> > incomplete message into ir-core. 
> 
> Yes, agreed. Sorry if I wasn't clear. I just wanted to make sure you've
> thought about what happens when the IR message is short (e.g. rc-5 with
> 23 pulse-spaces). Are the remaining registers 0 or do we get stale data
> from a previous transmit?

Before exit from this IRQ handler , mtk_w32_mask(ir, 0x1, MTK_IRCLR,
MTK_IRCLR_REG) would be done that causes all registers used to store 
pulses and spaces to be cleared, so no stale data appears in the next 
transmit.


> > But I was still afraid the state machine can't  go back to initial state
> > after receiving these incomplete data. 
> > 
> > So the ir_raw_event_reset() call in the beginning of ISR seems becoming
> > more important.
> > 
> > > > +	}
> > > > +
> > > > +	/* The maximum number of edges the IR controller can
> > > > +	 * hold is MTK_CHKDATA_SZ * 4. So if received IR messages
> > > > +	 * is over the limit, the last incomplete IR message would
> > > > +	 * be appended trailing space and still would be sent into
> > > > +	 * ir-rc-raw to decode. That helps it is possible that it
> > > > +	 * has enough information to decode a scancode even if the
> > > > +	 * trailing end of the message is missing.
> > > > +	 */
> > > > +	if (!MTK_IR_END(wid, rawir.pulse)) {
> > > > +		rawir.pulse = false;
> > > > +		rawir.duration = MTK_MAX_SAMPLES * (MTK_IR_SAMPLE + 1);
> > > > +		ir_raw_event_store_with_filter(ir->rc, &rawir);
> > > > +	}
> 
> See here you add a long space if one was not added already.
> 
> > > > +
> > > > +	ir_raw_event_handle(ir->rc);
> > > > +
> > > > +	/* Restart controller for the next receive */
> > > > +	mtk_w32_mask(ir, 0x1, MTK_IRCLR, MTK_IRCLR_REG);
> > > > +
> > > > +	/* Clear interrupt status */
> > > > +	mtk_w32_mask(ir, 0x1, MTK_IRINT_CLR, MTK_IRINT_CLR_REG);
> > > > +
> > > > +	/* Enable interrupt */
> > > > +	mtk_irq_enable(ir, MTK_IRINT_EN);
> > > > +
> > > > +	return IRQ_HANDLED;
> > > > +}
> > > > +
> > > > +static int mtk_ir_probe(struct platform_device *pdev)
> > > > +{
> > > > +	struct device *dev = &pdev->dev;
> > > > +	struct device_node *dn = dev->of_node;
> > > > +	struct resource *res;
> > > > +	struct mtk_ir *ir;
> > > > +	u32 val;
> > > > +	int ret = 0;
> > > > +	const char *map_name;
> > > > +
> > > > +	ir = devm_kzalloc(dev, sizeof(struct mtk_ir), GFP_KERNEL);
> > > > +	if (!ir)
> > > > +		return -ENOMEM;
> > > > +
> > > > +	ir->dev = dev;
> > > > +
> > > > +	if (!of_device_is_compatible(dn, "mediatek,mt7623-cir"))
> > > > +		return -ENODEV;
> > > > +
> > > > +	ir->clk = devm_clk_get(dev, "clk");
> > > > +	if (IS_ERR(ir->clk)) {
> > > > +		dev_err(dev, "failed to get a ir clock.\n");
> > > > +		return PTR_ERR(ir->clk);
> > > > +	}
> > > > +
> > > > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > > +	ir->base = devm_ioremap_resource(dev, res);
> > > > +	if (IS_ERR(ir->base)) {
> > > > +		dev_err(dev, "failed to map registers\n");
> > > > +		return PTR_ERR(ir->base);
> > > > +	}
> > > > +
> > > > +	ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
> > > > +	if (!ir->rc) {
> > > > +		dev_err(dev, "failed to allocate device\n");
> > > > +		return -ENOMEM;
> > > > +	}
> > > > +
> > > > +	ir->rc->priv = ir;
> > > > +	ir->rc->input_name = MTK_IR_DEV;
> > > > +	ir->rc->input_phys = MTK_IR_DEV "/input0";
> > > > +	ir->rc->input_id.bustype = BUS_HOST;
> > > > +	ir->rc->input_id.vendor = 0x0001;
> > > > +	ir->rc->input_id.product = 0x0001;
> > > > +	ir->rc->input_id.version = 0x0001;
> > > > +	map_name = of_get_property(dn, "linux,rc-map-name", NULL);
> > > > +	ir->rc->map_name = map_name ?: RC_MAP_EMPTY;
> > > > +	ir->rc->dev.parent = dev;
> > > > +	ir->rc->driver_name = MTK_IR_DEV;
> > > > +	ir->rc->allowed_protocols = RC_BIT_ALL;
> > > > +	ir->rc->rx_resolution = MTK_IR_SAMPLE;
> > > > +	ir->rc->timeout = MTK_MAX_SAMPLES * (MTK_IR_SAMPLE + 1);
> > > > +
> > > > +	ret = devm_rc_register_device(dev, ir->rc);
> > > 
> > > Here you do devm_rc_register_device()
> > 
> > does it have problem ?
> 
> Sorry, no. I just wanted to highlight wrt a comment below.
> > 
> > 
> > > > +	if (ret) {
> > > > +		dev_err(dev, "failed to register rc device\n");
> > > > +		return ret;
> > > > +	}
> > > > +
> > > > +	platform_set_drvdata(pdev, ir);
> > > > +
> > > > +	ir->irq = platform_get_irq(pdev, 0);
> > > > +	if (ir->irq < 0) {
> > > > +		dev_err(dev, "no irq resource\n");
> > > > +		return -ENODEV;
> > > > +	}
> > > > +
> > > > +	/* Enable interrupt after proper hardware
> > > > +	 * setup and IRQ handler registration
> > > > +	 */
> > > > +	if (clk_prepare_enable(ir->clk)) {
> > > > +		dev_err(dev, "try to enable ir_clk failed\n");
> > > > +		ret = -EINVAL;
> > > > +		goto exit_clkdisable_clk;
> > > > +	}
> > > > +
> > > > +	mtk_irq_disable(ir, MTK_IRINT_EN);
> > > > +
> > > > +	ret = devm_request_irq(dev, ir->irq, mtk_ir_irq, 0, MTK_IR_DEV, ir);
> > > > +	if (ret) {
> > > > +		dev_err(dev, "failed request irq\n");
> > > > +		goto exit_clkdisable_clk;
> > > > +	}
> > > > +
> > > > +	/* Enable IR and PWM */
> > > > +	val = mtk_r32(ir, MTK_CONFIG_HIGH_REG);
> > > > +	val |= MTK_PWM_EN | MTK_IR_EN;
> > > > +	mtk_w32(ir, val, MTK_CONFIG_HIGH_REG);
> > > > +
> > > > +	/* Setting sample period */
> > > > +	mtk_w32_mask(ir, MTK_CHK_PERIOD, MTK_CHK_PERIOD_MASK,
> > > > +		     MTK_CONFIG_LOW_REG);
> > > > +
> > > > +	mtk_irq_enable(ir, MTK_IRINT_EN);
> > > > +
> > > > +	dev_info(dev, "Initialized MT7623 IR driver, sample period = %luus\n",
> > > > +		 DIV_ROUND_CLOSEST(MTK_IR_SAMPLE, 1000));
> > > > +
> > > > +	return 0;
> > > > +
> > > > +exit_clkdisable_clk:
> > > > +	clk_disable_unprepare(ir->clk);
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int mtk_ir_remove(struct platform_device *pdev)
> > > > +{
> > > > +	struct mtk_ir *ir = platform_get_drvdata(pdev);
> > > > +
> > > > +	/* Avoid contention between remove handler and
> > > > +	 * IRQ handler so that disabling IR interrupt and
> > > > +	 * waiting for pending IRQ handler to complete
> > > > +	 */
> > > > +	mtk_irq_disable(ir, MTK_IRINT_EN);
> > > > +	synchronize_irq(ir->irq);
> > > > +
> > > > +	clk_disable_unprepare(ir->clk);
> > > > +
> > > > +	rc_unregister_device(ir->rc);
> > > 
> > > Yet here you explicitly call rc_unregister_device(). Since it was registered
> > > with the devm call, this call is not needed and will lead to double frees etc
> > 
> > bug :( .  I will fix it ..
> > 
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static const struct of_device_id mtk_ir_match[] = {
> > > > +	{ .compatible = "mediatek,mt7623-cir" },
> > > > +	{},
> > > > +};
> > > > +MODULE_DEVICE_TABLE(of, mtk_ir_match);
> > > > +
> > > > +static struct platform_driver mtk_ir_driver = {
> > > > +	.probe          = mtk_ir_probe,
> > > > +	.remove         = mtk_ir_remove,
> > > > +	.driver = {
> > > > +		.name = MTK_IR_DEV,
> > > > +		.of_match_table = mtk_ir_match,
> > > > +	},
> > > > +};
> > > > +
> > > > +module_platform_driver(mtk_ir_driver);
> > > > +
> > > > +MODULE_DESCRIPTION("Mediatek IR Receiver Controller Driver");
> > > > +MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>");
> > > > +MODULE_LICENSE("GPL");
> > > > -- 
> > > > 2.7.4
> > > > 
> > 
> > 
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-media" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v2 2/2] media: rc: add driver for IR remote receiver on MT7623 SoC

[Sean Wang]

okay, I will continue to work based on your changes unless someone else
has concerns

On Wed, 2017-01-11 at 07:45 +0900, Andi Shyti wrote:
> Hi Sean,
> 
> >    include/linux/compiler.h:253:8: sparse: attribute 'no_sanitize_address': unknown attribute
> > >> drivers/media/rc/mtk-cir.c:215:41: sparse: too many arguments for function devm_rc_allocate_device
> >    drivers/media/rc/mtk-cir.c: In function 'mtk_ir_probe':
> >    drivers/media/rc/mtk-cir.c:215:11: error: too many arguments to function 'devm_rc_allocate_device'
> >      ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
> >               ^~~~~~~~~~~~~~~~~~~~~~~
> >    In file included from drivers/media/rc/mtk-cir.c:22:0:
> >    include/media/rc-core.h:213:16: note: declared here
> >     struct rc_dev *devm_rc_allocate_device(struct device *dev);
> >                    ^~~~~~~~~~~~~~~~~~~~~~~
> > 
> > vim +/devm_rc_allocate_device +215 drivers/media/rc/mtk-cir.c
> > 
> >    209		ir->base = devm_ioremap_resource(dev, res);
> >    210		if (IS_ERR(ir->base)) {
> >    211			dev_err(dev, "failed to map registers\n");
> >    212			return PTR_ERR(ir->base);
> >    213		}
> >    214	
> >  > 215		ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
> 
> this error comes because the patches I pointed out have not been
> applied yet. I guess you can ignore them as long as you tested
> yours on top those patches.
> 
> Andi