From 371443de3c991f7b025d5203754a3497b7ea7c32 Mon Sep 17 00:00:00 2001 From: Sean Young Date: Tue, 10 Nov 2020 09:30:38 +0100 Subject: media: sunxi-cir: allow timeout to be set at runtime This allows the timeout to be set with the LIRC_SET_REC_TIMEOUT ioctl. The timeout was hardcoded at just over 20ms, but returned 120ms when queried with the LIRC_GET_REC_TIMEOUT ioctl. This also ensures the idle threshold is set correctly with a base clock other than 8Mhz. Acked-by: Maxime Ripard Signed-off-by: Sean Young Signed-off-by: Mauro Carvalho Chehab --- drivers/media/rc/sunxi-cir.c | 48 ++++++++++++++++++++++++++++++++++++-------- 1 file changed, 40 insertions(+), 8 deletions(-) (limited to 'drivers/media/rc') diff --git a/drivers/media/rc/sunxi-cir.c b/drivers/media/rc/sunxi-cir.c index 4afc5895bee7..8555c7798706 100644 --- a/drivers/media/rc/sunxi-cir.c +++ b/drivers/media/rc/sunxi-cir.c @@ -73,10 +73,6 @@ #define SUNXI_IR_BASE_CLK 8000000 /* Noise threshold in samples */ #define SUNXI_IR_RXNOISE 1 -/* Idle Threshold in samples */ -#define SUNXI_IR_RXIDLE 20 -/* Time after which device stops sending data in ms */ -#define SUNXI_IR_TIMEOUT 120 /** * struct sunxi_ir_quirks - Differences between SoC variants. @@ -146,6 +142,41 @@ static irqreturn_t sunxi_ir_irq(int irqno, void *dev_id) return IRQ_HANDLED; } +/* Convert idle threshold to usec */ +static unsigned int sunxi_ithr_to_usec(unsigned int base_clk, unsigned int ithr) +{ + return DIV_ROUND_CLOSEST(USEC_PER_SEC * (ithr + 1), + base_clk / (128 * 64)); +} + +/* Convert usec to idle threshold */ +static unsigned int sunxi_usec_to_ithr(unsigned int base_clk, unsigned int usec) +{ + /* make sure we don't end up with a timeout less than requested */ + return DIV_ROUND_UP((base_clk / (128 * 64)) * usec, USEC_PER_SEC) - 1; +} + +static int sunxi_ir_set_timeout(struct rc_dev *rc_dev, unsigned int timeout) +{ + struct sunxi_ir *ir = rc_dev->priv; + unsigned int base_clk = clk_get_rate(ir->clk); + unsigned long flags; + + unsigned int ithr = sunxi_usec_to_ithr(base_clk, timeout); + + dev_dbg(rc_dev->dev.parent, "setting idle threshold to %u\n", ithr); + + spin_lock_irqsave(&ir->ir_lock, flags); + /* Set noise threshold and idle threshold */ + writel(REG_CIR_NTHR(SUNXI_IR_RXNOISE) | REG_CIR_ITHR(ithr), + ir->base + SUNXI_IR_CIR_REG); + spin_unlock_irqrestore(&ir->ir_lock, flags); + + rc_dev->timeout = sunxi_ithr_to_usec(base_clk, ithr); + + return 0; +} + static int sunxi_ir_probe(struct platform_device *pdev) { int ret = 0; @@ -242,9 +273,11 @@ static int sunxi_ir_probe(struct platform_device *pdev) ir->rc->map_name = ir->map_name ?: RC_MAP_EMPTY; ir->rc->dev.parent = dev; ir->rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER; - /* Frequency after IR internal divider with sample period in ns */ + /* Frequency after IR internal divider with sample period in us */ ir->rc->rx_resolution = (USEC_PER_SEC / (b_clk_freq / 64)); - ir->rc->timeout = MS_TO_US(SUNXI_IR_TIMEOUT); + ir->rc->min_timeout = sunxi_ithr_to_usec(b_clk_freq, 0); + ir->rc->max_timeout = sunxi_ithr_to_usec(b_clk_freq, 255); + ir->rc->s_timeout = sunxi_ir_set_timeout; ir->rc->driver_name = SUNXI_IR_DEV; ret = rc_register_device(ir->rc); @@ -272,8 +305,7 @@ static int sunxi_ir_probe(struct platform_device *pdev) writel(REG_CTL_MD, ir->base+SUNXI_IR_CTL_REG); /* Set noise threshold and idle threshold */ - writel(REG_CIR_NTHR(SUNXI_IR_RXNOISE)|REG_CIR_ITHR(SUNXI_IR_RXIDLE), - ir->base + SUNXI_IR_CIR_REG); + sunxi_ir_set_timeout(ir->rc, IR_DEFAULT_TIMEOUT); /* Invert Input Signal */ writel(REG_RXCTL_RPPI, ir->base + SUNXI_IR_RXCTL_REG); -- cgit v1.2.3