Commit 5ad05eca authored by Sean Young's avatar Sean Young Committed by Mauro Carvalho Chehab
Browse files

media: gpio-ir-tx: fix transmit with long spaces on Orange Pi PC 



Calling udelay for than 1000us does not always yield the correct
results.

Cc: stable@vger.kernel.org
Reported-by: default avatarМихаил <vrserver1@gmail.com>
Signed-off-by: default avatarSean Young <sean@mess.org>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@kernel.org>
parent 10923471

drivers/media/rc/gpio-ir-tx.c

+21 −7
Original line number Diff line number Diff line
@@ -48,11 +48,29 @@ static int gpio_ir_tx_set_carrier(struct rc_dev *dev, u32 carrier) 
	return 0;

}



static void delay_until(ktime_t until)

{

	/*

	 * delta should never exceed 0.5 seconds (IR_MAX_DURATION) and on

	 * m68k ndelay(s64) does not compile; so use s32 rather than s64.

	 */

	s32 delta;



	while (true) {

		delta = ktime_us_delta(until, ktime_get());

		if (delta <= 0)

			return;



		/* udelay more than 1ms may not work */

		delta = min(delta, 1000);

		udelay(delta);

	}

}



static void gpio_ir_tx_unmodulated(struct gpio_ir *gpio_ir, uint *txbuf,

				   uint count)

{

	ktime_t edge;

	s32 delta;

	int i;



	local_irq_disable();
@@ -63,9 +81,7 @@ static void gpio_ir_tx_unmodulated(struct gpio_ir *gpio_ir, uint *txbuf, 
		gpiod_set_value(gpio_ir->gpio, !(i % 2));



		edge = ktime_add_us(edge, txbuf[i]);

		delta = ktime_us_delta(edge, ktime_get());

		if (delta > 0)

			udelay(delta);

		delay_until(edge);

	}



	gpiod_set_value(gpio_ir->gpio, 0);
@@ -97,9 +113,7 @@ static void gpio_ir_tx_modulated(struct gpio_ir *gpio_ir, uint *txbuf, 
		if (i % 2) {

			// space

			edge = ktime_add_us(edge, txbuf[i]);

			delta = ktime_us_delta(edge, ktime_get());

			if (delta > 0)

				udelay(delta);

			delay_until(edge);

		} else {

			// pulse

			ktime_t last = ktime_add_us(edge, txbuf[i]);