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Commit 169d1338 authored by Tomas Winkler's avatar Tomas Winkler Committed by Greg Kroah-Hartman
Browse files

mei: make mei_write_message more readable 



1. reduce hairy casting
2. replace open code with mei_count_empty_write_slots
4. include header size in check for overflow
3. use concise for loop instead of a while loop

Signed-off-by: default avatarTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent d2041158

drivers/misc/mei/interface.c

+18 −31
Original line number Diff line number Diff line
@@ -127,52 +127,39 @@ int mei_count_empty_write_slots(struct mei_device *dev) 
 *

 * This function returns -EIO if write has failed

 */

int mei_write_message(struct mei_device *dev,

		      struct mei_msg_hdr *header,

		      unsigned char *write_buffer,

		      unsigned long write_length)

int mei_write_message(struct mei_device *dev, struct mei_msg_hdr *header,

		      unsigned char *buf, unsigned long length)

{

	u32 temp_msg = 0;

	unsigned long bytes_written = 0;

	unsigned char buffer_depth, filled_slots, empty_slots;

	unsigned long dw_to_write;



	dev->host_hw_state = mei_hcsr_read(dev);

	unsigned long rem, dw_cnt;

	u32 *reg_buf = (u32 *)buf;

	int i;

	int empty_slots;



	dev_dbg(&dev->pdev->dev,

			"host_hw_state = 0x%08x.\n",

			dev->host_hw_state);



	dev_dbg(&dev->pdev->dev,

			"mei_write_message header=%08x.\n",

			*((u32 *) header));



	buffer_depth = (unsigned char) ((dev->host_hw_state & H_CBD) >> 24);

	filled_slots = _host_get_filled_slots(dev);

	empty_slots = buffer_depth - filled_slots;

	dev_dbg(&dev->pdev->dev,

			"filled = %hu, empty = %hu.\n",

			filled_slots, empty_slots);



	dw_to_write = ((write_length + 3) / 4);

	empty_slots = mei_count_empty_write_slots(dev);

	dev_dbg(&dev->pdev->dev, "empty slots = %hu.\n", empty_slots);



	if (dw_to_write > empty_slots)

	dw_cnt = (length + sizeof(*header) + 3) / 4;

	if (empty_slots < 0 || dw_cnt > empty_slots)

		return -EIO;



	mei_reg_write(dev, H_CB_WW, *((u32 *) header));



	while (write_length >= 4) {

		mei_reg_write(dev, H_CB_WW,

				*(u32 *) (write_buffer + bytes_written));

		bytes_written += 4;

		write_length -= 4;

	}

	for (i = 0; i < length / 4; i++)

		mei_reg_write(dev, H_CB_WW, reg_buf[i]);



	if (write_length > 0) {

		memcpy(&temp_msg, &write_buffer[bytes_written], write_length);

		mei_reg_write(dev, H_CB_WW, temp_msg);

	rem = length & 0x3;

	if (rem > 0) {

		u32 reg = 0;

		memcpy(&reg, &buf[length - rem], rem);

		mei_reg_write(dev, H_CB_WW, reg);

	}



	dev->host_hw_state = mei_hcsr_read(dev);

	dev->host_hw_state |= H_IG;

	mei_hcsr_set(dev);

	dev->me_hw_state = mei_mecsr_read(dev);