[PATCH] nuvoton-cir: Add support for user configurable wake-up codes

["Antti Seppälä" <a.seppala@gmail.com>]

This patch introduces module parameters for setting wake-up codes to be
programmed into the hardware FIFO. This allows users to provide custom
IR sample sequences to trigger system wake-up from sleep states.

Usage:
   modprobe nuvoton-cir wake_samples=0x90,0x11,0xa1... (up to 67 bytes)

Here is a summary of module parameters introduced by this patch:
 * wake_samples: FIFO values to compare against received IR codes when
   in sleep state.

 * cmp_deep: Number of bytes the hardware will compare against. This is
   currently autodetected by the driver.

 * cmp_tolerance: The maximum allowed value difference between a single
   wake-up byte and a sample read from IR to be still considered a match.
   Default is 5.

Signed-off-by: Antti Seppälä <a.seppala@gmail.com>
---
 drivers/media/rc/nuvoton-cir.c | 65 +++++++++++++++++++++++++++++++-----------
 drivers/media/rc/nuvoton-cir.h |  6 ++--
 2 files changed, 51 insertions(+), 20 deletions(-)

diff --git a/drivers/media/rc/nuvoton-cir.c b/drivers/media/rc/nuvoton-cir.c
index 21ee0dc..b11ee43 100644
--- a/drivers/media/rc/nuvoton-cir.c
+++ b/drivers/media/rc/nuvoton-cir.c
@@ -39,6 +39,15 @@
 
 #include "nuvoton-cir.h"
 
+/* debugging module parameter */
+static int debug;
+
+/* Wake up configuration parameters */
+static unsigned char wake_samples[WAKE_FIFO_LEN];
+static unsigned int num_wake_samples;
+static unsigned char cmp_deep;
+static unsigned char cmp_tolerance = CIR_WAKE_CMP_TOLERANCE;
+
 /* write val to config reg */
 static inline void nvt_cr_write(struct nvt_dev *nvt, u8 val, u8 reg)
 {
@@ -418,13 +427,38 @@ static void nvt_cir_regs_init(struct nvt_dev *nvt)
 
 static void nvt_cir_wake_regs_init(struct nvt_dev *nvt)
 {
+	int i;
+	u8 cmp_reg = CIR_WAKE_FIFO_CMP_BYTES;
+	u8 ircon_reg = CIR_WAKE_IRCON_RXEN | CIR_WAKE_IRCON_R |
+		       CIR_WAKE_IRCON_RXINV | CIR_WAKE_IRCON_SAMPLE_PERIOD_SEL;
+	/*
+	 * Enable TX and RX, specific carrier on = low, off = high, and set
+	 * sample period (currently 50us)
+	 */
+	nvt_cir_wake_reg_write(nvt, ircon_reg | CIR_WAKE_IRCON_MODE1,
+			       CIR_WAKE_IRCON);
+
+	/* clear cir wake rx fifo */
+	nvt_clear_cir_wake_fifo(nvt);
+
+	/* Write samples from module parameter to fifo */
+	for (i = 0; i < num_wake_samples; i++)
+		nvt_cir_wake_reg_write(nvt, wake_samples[i],
+				       CIR_WAKE_WR_FIFO_DATA);
+
+	/* Switch cir to wakeup mode and disable fifo writing */
+	nvt_cir_wake_reg_write(nvt, ircon_reg | CIR_WAKE_IRCON_MODE0,
+			       CIR_WAKE_IRCON);
+
 	/* set number of bytes needed for wake from s3 (default 65) */
-	nvt_cir_wake_reg_write(nvt, CIR_WAKE_FIFO_CMP_BYTES,
-			       CIR_WAKE_FIFO_CMP_DEEP);
+	if (cmp_deep)
+		cmp_reg = cmp_deep;
+	else if (num_wake_samples)
+		cmp_reg = num_wake_samples;
+	nvt_cir_wake_reg_write(nvt, cmp_reg, CIR_WAKE_FIFO_CMP_DEEP);
 
 	/* set tolerance/variance allowed per byte during wake compare */
-	nvt_cir_wake_reg_write(nvt, CIR_WAKE_CMP_TOLERANCE,
-			       CIR_WAKE_FIFO_CMP_TOL);
+	nvt_cir_wake_reg_write(nvt, cmp_tolerance, CIR_WAKE_FIFO_CMP_TOL);
 
 	/* set sample limit count (PE interrupt raised when reached) */
 	nvt_cir_wake_reg_write(nvt, CIR_RX_LIMIT_COUNT >> 8, CIR_WAKE_SLCH);
@@ -434,18 +468,6 @@ static void nvt_cir_wake_regs_init(struct nvt_dev *nvt)
 	nvt_cir_wake_reg_write(nvt, CIR_WAKE_FIFOCON_RX_TRIGGER_LEV,
 			       CIR_WAKE_FIFOCON);
 
-	/*
-	 * Enable TX and RX, specific carrier on = low, off = high, and set
-	 * sample period (currently 50us)
-	 */
-	nvt_cir_wake_reg_write(nvt, CIR_WAKE_IRCON_MODE0 | CIR_WAKE_IRCON_RXEN |
-			       CIR_WAKE_IRCON_R | CIR_WAKE_IRCON_RXINV |
-			       CIR_WAKE_IRCON_SAMPLE_PERIOD_SEL,
-			       CIR_WAKE_IRCON);
-
-	/* clear cir wake rx fifo */
-	nvt_clear_cir_wake_fifo(nvt);
-
 	/* clear any and all stray interrupts */
 	nvt_cir_wake_reg_write(nvt, 0xff, CIR_WAKE_IRSTS);
 }
@@ -1232,6 +1254,17 @@ static void nvt_exit(void)
 module_param(debug, int, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(debug, "Enable debugging output");
 
+module_param_array(wake_samples, byte, &num_wake_samples, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(wake_samples, "FIFO sample bytes triggering wake");
+
+module_param(cmp_deep, byte, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(cmp_deep, "How many bytes need to compare\n"
+			   "\t\t(0 = auto (default))");
+
+module_param(cmp_tolerance, byte, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(cmp_tolerance, "Data tolerance to each wake sample byte\n"
+				"\t\t(default = 5)");
+
 MODULE_DEVICE_TABLE(pnp, nvt_ids);
 MODULE_DESCRIPTION("Nuvoton W83667HG-A & W83677HG-I CIR driver");
 
diff --git a/drivers/media/rc/nuvoton-cir.h b/drivers/media/rc/nuvoton-cir.h
index 07e8310..8209f84 100644
--- a/drivers/media/rc/nuvoton-cir.h
+++ b/drivers/media/rc/nuvoton-cir.h
@@ -31,10 +31,6 @@
 /* platform driver name to register */
 #define NVT_DRIVER_NAME "nuvoton-cir"
 
-/* debugging module parameter */
-static int debug;
-
-
 #define nvt_pr(level, text, ...) \
 	printk(level KBUILD_MODNAME ": " text, ## __VA_ARGS__)
 
@@ -64,6 +60,8 @@ static int debug;
 #define TX_BUF_LEN 256
 #define RX_BUF_LEN 32
 
+#define WAKE_FIFO_LEN 67
+
 struct nvt_dev {
 	struct pnp_dev *pdev;
 	struct rc_dev *rdev;
-- 
1.8.3.2