On Tue, Dec 19, 2017 at 09:07:42AM +0100, Philipp Rossak wrote:
> This patch updates the sunxi-ir driver to set the base clock frequency from
> devicetree.
>
> This is necessary since there are different ir receivers on the
> market, that operate with different frequencies. So this value could be
> set if the attached ir receiver needs a different base clock frequency,
> than the default 8 MHz.
>
> Signed-off-by: Philipp Rossak <embe...@gmail.com>
Acked-by: Sean Young <s...@mess.org>
Sean
> ---
> drivers/media/rc/sunxi-cir.c | 19 +++++++++++--------
> 1 file changed, 11 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/media/rc/sunxi-cir.c b/drivers/media/rc/sunxi-cir.c
> index 97f367b446c4..f500cea228a9 100644
> --- a/drivers/media/rc/sunxi-cir.c
> +++ b/drivers/media/rc/sunxi-cir.c
> @@ -72,12 +72,8 @@
> /* CIR_REG register idle threshold */
> #define REG_CIR_ITHR(val) (((val) << 8) & (GENMASK(15, 8)))
>
> -/* Required frequency for IR0 or IR1 clock in CIR mode */
> +/* Required frequency for IR0 or IR1 clock in CIR mode (default) */
> #define SUNXI_IR_BASE_CLK 8000000
> -/* Frequency after IR internal divider */
> -#define SUNXI_IR_CLK (SUNXI_IR_BASE_CLK / 64)
> -/* Sample period in ns */
> -#define SUNXI_IR_SAMPLE (1000000000ul / SUNXI_IR_CLK)
> /* Noise threshold in samples */
> #define SUNXI_IR_RXNOISE 1
> /* Idle Threshold in samples */
> @@ -122,7 +118,8 @@ static irqreturn_t sunxi_ir_irq(int irqno, void *dev_id)
> /* for each bit in fifo */
> dt = readb(ir->base + SUNXI_IR_RXFIFO_REG);
> rawir.pulse = (dt & 0x80) != 0;
> - rawir.duration = ((dt & 0x7f) + 1) * SUNXI_IR_SAMPLE;
> + rawir.duration = ((dt & 0x7f) + 1) *
> + ir->rc->rx_resolution;
> ir_raw_event_store_with_filter(ir->rc, &rawir);
> }
> }
> @@ -148,6 +145,7 @@ static int sunxi_ir_probe(struct platform_device *pdev)
> struct device_node *dn = dev->of_node;
> struct resource *res;
> struct sunxi_ir *ir;
> + u32 b_clk_freq = SUNXI_IR_BASE_CLK;
>
> ir = devm_kzalloc(dev, sizeof(struct sunxi_ir), GFP_KERNEL);
> if (!ir)
> @@ -172,6 +170,9 @@ static int sunxi_ir_probe(struct platform_device *pdev)
> return PTR_ERR(ir->clk);
> }
>
> + /* Base clock frequency (optional) */
> + of_property_read_u32(dn, "clock-frequency", &b_clk_freq);
> +
> /* Reset (optional) */
> ir->rst = devm_reset_control_get_optional_exclusive(dev, NULL);
> if (IS_ERR(ir->rst))
> @@ -180,11 +181,12 @@ static int sunxi_ir_probe(struct platform_device *pdev)
> if (ret)
> return ret;
>
> - ret = clk_set_rate(ir->clk, SUNXI_IR_BASE_CLK);
> + ret = clk_set_rate(ir->clk, b_clk_freq);
> if (ret) {
> dev_err(dev, "set ir base clock failed!\n");
> goto exit_reset_assert;
> }
> + dev_dbg(dev, "set base clock frequency to %d Hz.\n", b_clk_freq);
>
> if (clk_prepare_enable(ir->apb_clk)) {
> dev_err(dev, "try to enable apb_ir_clk failed\n");
> @@ -225,7 +227,8 @@ 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;
> - ir->rc->rx_resolution = SUNXI_IR_SAMPLE;
> + /* Frequency after IR internal divider with sample period in ns */
> + ir->rc->rx_resolution = (1000000000ul / (b_clk_freq / 64));
> ir->rc->timeout = MS_TO_NS(SUNXI_IR_TIMEOUT);
> ir->rc->driver_name = SUNXI_IR_DEV;
>
> --
> 2.11.0
