[media] au0828: speed up i2c clock when doing xc5000 firmware load (faaf01b2) · Commits · 戴 / test

Put a hack in place to speed up the firmware load in the case that the xc5000 has just been reset. The chip can safely do 400 KHz in this mode, while in normal operation it can only do 100 KHz. This reduces the firmware load time from 6.9 seconds to 4.2. Signed-off-by:

Devin Heitmueller <dheitmueller@kernellabs.com> Signed-off-by:

Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/au0828/au0828-i2c.c

+13 −3

Original line number	Diff line number	Diff line
		@@ -26,7 +26,7 @@
		#include <linux/io.h>

		#include "au0828.h"

		#include "media/tuner.h"
		#include <media/v4l2-common.h>

		static int i2c_scan;
		@@ -147,8 +147,18 @@ static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
		au0828_write(dev, AU0828_I2C_MULTIBYTE_MODE_2FF, 0x01);

		/* Set the I2C clock */
		if ((dev->board.tuner_type == TUNER_XC5000) &&
		(dev->board.tuner_addr == msg->addr) &&
		(msg->len == 64)) {
		/* Hack to speed up firmware load. The xc5000 lets us do up
		to 400 KHz when in firmware download mode */
		au0828_write(dev, AU0828_I2C_CLK_DIVIDER_202,
		AU0828_I2C_CLK_250KHZ);
		} else {
		/* Use the i2c clock speed in the board configuration */
		au0828_write(dev, AU0828_I2C_CLK_DIVIDER_202,
		dev->board.i2c_clk_divider);
		}

		/* Hardware needs 8 bit addresses */
		au0828_write(dev, AU0828_I2C_DEST_ADDR_203, msg->addr << 1);

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