[ 43/47] spi-topcliff-pch: Fix issue for transmitting over 4KByte

From: Greg KH
Date: Fri May 18 2012 - 19:09:46 EST


3.3-stable review patch. If anyone has any objections, please let me know.

------------------

From: Tomoya MORINAGA <tomoya.rohm@xxxxxxxxx>

commit 7d05b3e868ee0f9231baf40cb77be3df5dd1f18c upstream.

Currently, when spi-topcliff-pch receives transmit request over 4KByte,
this driver can't process correctly. This driver needs to divide the data
into 4Kbyte unit.
This patch fixes the issue.

Signed-off-by: Tomoya MORINAGA <tomoya.rohm@xxxxxxxxx>
Signed-off-by: Grant Likely <grant.likely@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/spi/spi-topcliff-pch.c | 66 ++++++++++++++++++++++++++++++++++-------
1 file changed, 55 insertions(+), 11 deletions(-)

--- a/drivers/spi/spi-topcliff-pch.c
+++ b/drivers/spi/spi-topcliff-pch.c
@@ -196,6 +196,7 @@ struct pch_spi_data {
struct pch_spi_dma_ctrl dma;
int use_dma;
u8 irq_reg_sts;
+ int save_total_len;
};

/**
@@ -823,11 +824,13 @@ static void pch_spi_copy_rx_data_for_dma
rx_dma_buf = data->dma.rx_buf_virt;
for (j = 0; j < data->bpw_len; j++)
*rx_buf++ = *rx_dma_buf++ & 0xFF;
+ data->cur_trans->rx_buf = rx_buf;
} else {
rx_sbuf = data->cur_trans->rx_buf;
rx_dma_sbuf = data->dma.rx_buf_virt;
for (j = 0; j < data->bpw_len; j++)
*rx_sbuf++ = *rx_dma_sbuf++;
+ data->cur_trans->rx_buf = rx_sbuf;
}
}

@@ -853,6 +856,9 @@ static int pch_spi_start_transfer(struct
rtn = wait_event_interruptible_timeout(data->wait,
data->transfer_complete,
msecs_to_jiffies(2 * HZ));
+ if (!rtn)
+ dev_err(&data->master->dev,
+ "%s wait-event timeout\n", __func__);

dma_sync_sg_for_cpu(&data->master->dev, dma->sg_rx_p, dma->nent,
DMA_FROM_DEVICE);
@@ -989,6 +995,7 @@ static void pch_spi_handle_dma(struct pc
int i;
int size;
int rem;
+ int head;
unsigned long flags;
struct pch_spi_dma_ctrl *dma;

@@ -1017,6 +1024,11 @@ static void pch_spi_handle_dma(struct pc
}
data->bpw_len = data->cur_trans->len / (*bpw / 8);

+ if (data->bpw_len > PCH_BUF_SIZE) {
+ data->bpw_len = PCH_BUF_SIZE;
+ data->cur_trans->len -= PCH_BUF_SIZE;
+ }
+
/* copy Tx Data */
if (data->cur_trans->tx_buf != NULL) {
if (*bpw == 8) {
@@ -1031,10 +1043,17 @@ static void pch_spi_handle_dma(struct pc
*tx_dma_sbuf++ = *tx_sbuf++;
}
}
+
+ /* Calculate Rx parameter for DMA transmitting */
if (data->bpw_len > PCH_DMA_TRANS_SIZE) {
- num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
+ if (data->bpw_len % PCH_DMA_TRANS_SIZE) {
+ num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
+ rem = data->bpw_len % PCH_DMA_TRANS_SIZE;
+ } else {
+ num = data->bpw_len / PCH_DMA_TRANS_SIZE;
+ rem = PCH_DMA_TRANS_SIZE;
+ }
size = PCH_DMA_TRANS_SIZE;
- rem = data->bpw_len % PCH_DMA_TRANS_SIZE;
} else {
num = 1;
size = data->bpw_len;
@@ -1094,15 +1113,23 @@ static void pch_spi_handle_dma(struct pc
dma->nent = num;
dma->desc_rx = desc_rx;

- /* TX */
- if (data->bpw_len > PCH_DMA_TRANS_SIZE) {
- num = data->bpw_len / PCH_DMA_TRANS_SIZE;
+ /* Calculate Tx parameter for DMA transmitting */
+ if (data->bpw_len > PCH_MAX_FIFO_DEPTH) {
+ head = PCH_MAX_FIFO_DEPTH - PCH_DMA_TRANS_SIZE;
+ if (data->bpw_len % PCH_DMA_TRANS_SIZE > 4) {
+ num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
+ rem = data->bpw_len % PCH_DMA_TRANS_SIZE - head;
+ } else {
+ num = data->bpw_len / PCH_DMA_TRANS_SIZE;
+ rem = data->bpw_len % PCH_DMA_TRANS_SIZE +
+ PCH_DMA_TRANS_SIZE - head;
+ }
size = PCH_DMA_TRANS_SIZE;
- rem = 16;
} else {
num = 1;
size = data->bpw_len;
rem = data->bpw_len;
+ head = 0;
}

dma->sg_tx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
@@ -1112,11 +1139,17 @@ static void pch_spi_handle_dma(struct pc
for (i = 0; i < num; i++, sg++) {
if (i == 0) {
sg->offset = 0;
+ sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size + head,
+ sg->offset);
+ sg_dma_len(sg) = size + head;
+ } else if (i == (num - 1)) {
+ sg->offset = head + size * i;
+ sg->offset = sg->offset * (*bpw / 8);
sg_set_page(sg, virt_to_page(dma->tx_buf_virt), rem,
sg->offset);
sg_dma_len(sg) = rem;
} else {
- sg->offset = rem + size * (i - 1);
+ sg->offset = head + size * i;
sg->offset = sg->offset * (*bpw / 8);
sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size,
sg->offset);
@@ -1204,6 +1237,7 @@ static void pch_spi_process_messages(str
data->current_msg->spi->bits_per_word);
pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
do {
+ int cnt;
/* If we are already processing a message get the next
transfer structure from the message otherwise retrieve
the 1st transfer request from the message. */
@@ -1223,11 +1257,20 @@ static void pch_spi_process_messages(str
}
spin_unlock(&data->lock);

+ if (!data->cur_trans->len)
+ goto out;
+ cnt = (data->cur_trans->len - 1) / PCH_BUF_SIZE + 1;
+ data->save_total_len = data->cur_trans->len;
if (data->use_dma) {
- pch_spi_handle_dma(data, &bpw);
- if (!pch_spi_start_transfer(data))
- goto out;
- pch_spi_copy_rx_data_for_dma(data, bpw);
+ int i;
+ char *save_rx_buf = data->cur_trans->rx_buf;
+ for (i = 0; i < cnt; i ++) {
+ pch_spi_handle_dma(data, &bpw);
+ if (!pch_spi_start_transfer(data))
+ goto out;
+ pch_spi_copy_rx_data_for_dma(data, bpw);
+ }
+ data->cur_trans->rx_buf = save_rx_buf;
} else {
pch_spi_set_tx(data, &bpw);
pch_spi_set_ir(data);
@@ -1238,6 +1281,7 @@ static void pch_spi_process_messages(str
data->pkt_tx_buff = NULL;
}
/* increment message count */
+ data->cur_trans->len = data->save_total_len;
data->current_msg->actual_length += data->cur_trans->len;

dev_dbg(&data->master->dev,


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/