Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 31bc2c9b authored by Rui Miguel Silva's avatar Rui Miguel Silva Committed by Greg Kroah-Hartman
Browse files

greybus: spi: fix transfers bigger than greybus payload 



Add helper functions calculate the tx and rx size possible that fit a
greybus payload size and change the operation creation to adjust to that.

Signed-off-by: default avatarRui Miguel Silva <rui.silva@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@google.com>
parent 11aa7121

drivers/staging/greybus/spi.c

+87 −15
Original line number Original line Diff line number Diff line
@@ -31,6 +31,51 @@ static struct spi_master *get_master_from_spi(struct gb_spi *spi) 
	return spi->connection->private;

	return spi->connection->private;

}

}





static int tx_header_fit_operation(u32 tx_size, u32 count, size_t data_max)

{

	size_t headers_size;



	data_max -= sizeof(struct gb_spi_transfer_request);

	headers_size = (count + 1) * sizeof(struct gb_spi_transfer);



	return tx_size + headers_size > data_max ? 0 : 1;

}



static size_t calc_rx_xfer_size(u32 rx_size, u32 *tx_xfer_size, u32 len,

				size_t data_max)

{

	size_t rx_xfer_size;



	data_max -= sizeof(struct gb_spi_transfer_response);



	if (rx_size + len > data_max)

		rx_xfer_size = data_max - rx_size;

	else

		rx_xfer_size = len;



	/* if this is a write_read, for symmetry read the same as write */

	if (*tx_xfer_size && rx_xfer_size > *tx_xfer_size)

		rx_xfer_size = *tx_xfer_size;

	if (*tx_xfer_size && rx_xfer_size < *tx_xfer_size)

		*tx_xfer_size = rx_xfer_size;



	return rx_xfer_size;

}



static size_t calc_tx_xfer_size(u32 tx_size, u32 count, size_t len,

				size_t data_max)

{

	size_t headers_size;



	data_max -= sizeof(struct gb_spi_transfer_request);

	headers_size = (count + 1) * sizeof(struct gb_spi_transfer);



	if (tx_size + headers_size + len > data_max)

		return data_max - (tx_size + sizeof(struct gb_spi_transfer));



	return len;

}



/* Routines to transfer data */

/* Routines to transfer data */

static struct gb_operation *

static struct gb_operation *

gb_spi_operation_create(struct gb_connection *connection,

gb_spi_operation_create(struct gb_connection *connection,
@@ -41,9 +86,14 @@ gb_spi_operation_create(struct gb_connection *connection, 
	struct spi_transfer *xfer;

	struct spi_transfer *xfer;

	struct gb_spi_transfer *gb_xfer;

	struct gb_spi_transfer *gb_xfer;

	struct gb_operation *operation;

	struct gb_operation *operation;

	u32 tx_size = 0, rx_size = 0, count = 0, request_size;

	struct spi_transfer *last_xfer = NULL;

	u32 tx_size = 0, rx_size = 0, count = 0, xfer_len = 0, request_size;

	u32 tx_xfer_size = 0, rx_xfer_size = 0, last_xfer_size = 0;

	size_t data_max;

	void *tx_data;

	void *tx_data;





	data_max = gb_operation_get_payload_size_max(connection);



	/* Find number of transfers queued and tx/rx length in the message */

	/* Find number of transfers queued and tx/rx length in the message */

	list_for_each_entry(xfer, &msg->transfers, transfer_list) {

	list_for_each_entry(xfer, &msg->transfers, transfer_list) {

		if (!xfer->tx_buf && !xfer->rx_buf) {

		if (!xfer->tx_buf && !xfer->rx_buf) {
@@ -51,21 +101,33 @@ gb_spi_operation_create(struct gb_connection *connection, 
				"bufferless transfer, length %u\n", xfer->len);

				"bufferless transfer, length %u\n", xfer->len);

			return NULL;

			return NULL;

		}

		}

		last_xfer = xfer;





		if (xfer->tx_buf)

		tx_xfer_size = 0;

			tx_size += xfer->len;

		rx_xfer_size = 0;

		if (xfer->rx_buf)

			rx_size += xfer->len;





		*total_len += xfer->len;

		if (xfer->tx_buf) {

		count++;

			if (!tx_header_fit_operation(tx_size, count, data_max))

				break;

			tx_xfer_size = calc_tx_xfer_size(tx_size, count,

							 xfer->len, data_max);

			last_xfer_size = tx_xfer_size;

		}

		}





	/* Too many transfers ? */

		if (xfer->rx_buf) {

	if (count > (u32)U16_MAX) {

			rx_xfer_size = calc_rx_xfer_size(rx_size, &tx_xfer_size,

		dev_err(&connection->bundle->dev,

							 xfer->len, data_max);

			"transfer count (%u) too big\n", count);

			last_xfer_size = rx_xfer_size;

		return NULL;

		}



		tx_size += tx_xfer_size;

		rx_size += rx_xfer_size;



		*total_len += last_xfer_size;

		count++;



		if (xfer->len != last_xfer_size)

			break;

	}

	}





	/*

	/*
@@ -92,20 +154,30 @@ gb_spi_operation_create(struct gb_connection *connection, 




	/* Fill in the transfers array */

	/* Fill in the transfers array */

	list_for_each_entry(xfer, &msg->transfers, transfer_list) {

	list_for_each_entry(xfer, &msg->transfers, transfer_list) {

		if (last_xfer && xfer == last_xfer)

			xfer_len = last_xfer_size;

		else

			xfer_len = xfer->len;



		gb_xfer->speed_hz = cpu_to_le32(xfer->speed_hz);

		gb_xfer->speed_hz = cpu_to_le32(xfer->speed_hz);

		gb_xfer->len = cpu_to_le32(xfer->len);

		gb_xfer->len = cpu_to_le32(xfer_len);

		gb_xfer->delay_usecs = cpu_to_le16(xfer->delay_usecs);

		gb_xfer->delay_usecs = cpu_to_le16(xfer->delay_usecs);

		gb_xfer->cs_change = xfer->cs_change;

		gb_xfer->cs_change = xfer->cs_change;

		gb_xfer->bits_per_word = xfer->bits_per_word;

		gb_xfer->bits_per_word = xfer->bits_per_word;





		/* Copy tx data */

		/* Copy tx data */

		if (xfer->tx_buf) {

		if (xfer->tx_buf) {

			memcpy(tx_data, xfer->tx_buf, xfer->len);

			tx_data += xfer->len;

			gb_xfer->rdwr |= GB_SPI_XFER_WRITE;

			gb_xfer->rdwr |= GB_SPI_XFER_WRITE;

			memcpy(tx_data, xfer->tx_buf, xfer_len);

			tx_data += xfer_len;

		}

		}



		if (xfer->rx_buf)

		if (xfer->rx_buf)

			gb_xfer->rdwr |= GB_SPI_XFER_READ;

			gb_xfer->rdwr |= GB_SPI_XFER_READ;



		if (last_xfer && xfer == last_xfer)

			break;



		gb_xfer++;

		gb_xfer++;

	}

	}