Hi Roja,
On 12/3/2020 4:01 PM, Roja Rani Yarubandi wrote:
Store DMA mapping data in geni_i2c_dev struct to enhance DMA mapping
data scope. For example during shutdown callback to unmap DMA mapping,
this stored DMA mapping data can be used to call geni_se_tx_dma_unprep
and geni_se_rx_dma_unprep functions.
Add two helper functions geni_i2c_rx_msg_cleanup and
geni_i2c_tx_msg_cleanup to unwrap the things after rx/tx FIFO/DMA
transfers, so that the same can be used in geni_i2c_stop_xfer()
function during shutdown callback.
Signed-off-by: Roja Rani Yarubandi <rojay@xxxxxxxxxxxxxx>
---
Changes in V5:
- As per Stephen's comments separated this patch from shutdown
callback patch, gi2c->cur = NULL is not removed from
geni_i2c_abort_xfer(), and made a copy of gi2c->cur and passed
to cleanup functions.
Changes in V6:
- Added spin_lock/unlock in geni_i2c_rx_msg_cleanup() and
geni_i2c_tx_msg_cleanup() functions.
drivers/i2c/busses/i2c-qcom-geni.c | 69 +++++++++++++++++++++++-------
1 file changed, 53 insertions(+), 16 deletions(-)
diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
index dce75b85253c..bfbc80f65006 100644
--- a/drivers/i2c/busses/i2c-qcom-geni.c
+++ b/drivers/i2c/busses/i2c-qcom-geni.c
@@ -86,6 +86,9 @@ struct geni_i2c_dev {
u32 clk_freq_out;
const struct geni_i2c_clk_fld *clk_fld;
int suspended;
+ void *dma_buf;
+ size_t xfer_len;
+ dma_addr_t dma_addr;
};
struct geni_i2c_err_log {
@@ -348,14 +351,49 @@ static void geni_i2c_tx_fsm_rst(struct geni_i2c_dev *gi2c)
dev_err(gi2c->se.dev, "Timeout resetting TX_FSM\n");
}
+static void geni_i2c_rx_msg_cleanup(struct geni_i2c_dev *gi2c,
+ struct i2c_msg *cur)
+{
+ struct geni_se *se = &gi2c->se;
+ unsigned long flags;
+
+ spin_lock_irqsave(&gi2c->lock, flags);
+ gi2c->cur_rd = 0;
+ if (gi2c->dma_buf) {
+ if (gi2c->err)
+ geni_i2c_rx_fsm_rst(gi2c);
Which race we are trying to avoid here by holding spinlock?
We cannot call any sleeping API by holding spinlock, geni_i2c_rx_fsm_rst
calls *wait-for-completion*, which is a sleeping call.
+ geni_se_rx_dma_unprep(se, gi2c->dma_addr, gi2c->xfer_len);
+ i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err);
+ }
+ spin_unlock_irqrestore(&gi2c->lock, flags);
+}
+
+static void geni_i2c_tx_msg_cleanup(struct geni_i2c_dev *gi2c,
+ struct i2c_msg *cur)
+{
+ struct geni_se *se = &gi2c->se;
+ unsigned long flags;
+
+ spin_lock_irqsave(&gi2c->lock, flags);
+ gi2c->cur_wr = 0;
+ if (gi2c->dma_buf) {
+ if (gi2c->err)
+ geni_i2c_tx_fsm_rst(gi2c);
Same here
Regards,
Akash
+ geni_se_tx_dma_unprep(se, gi2c->dma_addr, gi2c->xfer_len);
+ i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err);
+ }
+ spin_unlock_irqrestore(&gi2c->lock, flags);
+}
+
static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
u32 m_param)
{
- dma_addr_t rx_dma;
+ dma_addr_t rx_dma = 0;
unsigned long time_left;
void *dma_buf = NULL;
struct geni_se *se = &gi2c->se;
size_t len = msg->len;
+ struct i2c_msg *cur;
if (!of_machine_is_compatible("lenovo,yoga-c630"))
dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
@@ -372,19 +410,18 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
geni_se_select_mode(se, GENI_SE_FIFO);
i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
dma_buf = NULL;
+ } else {
+ gi2c->xfer_len = len;
+ gi2c->dma_addr = rx_dma;
+ gi2c->dma_buf = dma_buf;
}
+ cur = gi2c->cur;
time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
if (!time_left)
geni_i2c_abort_xfer(gi2c);
- gi2c->cur_rd = 0;
- if (dma_buf) {
- if (gi2c->err)
- geni_i2c_rx_fsm_rst(gi2c);
- geni_se_rx_dma_unprep(se, rx_dma, len);
- i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err);
- }
+ geni_i2c_rx_msg_cleanup(gi2c, cur);
return gi2c->err;
}
@@ -392,11 +429,12 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
u32 m_param)
{
- dma_addr_t tx_dma;
+ dma_addr_t tx_dma = 0;
unsigned long time_left;
void *dma_buf = NULL;
struct geni_se *se = &gi2c->se;
size_t len = msg->len;
+ struct i2c_msg *cur;
if (!of_machine_is_compatible("lenovo,yoga-c630"))
dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
@@ -413,22 +451,21 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
geni_se_select_mode(se, GENI_SE_FIFO);
i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
dma_buf = NULL;
+ } else {
+ gi2c->xfer_len = len;
+ gi2c->dma_addr = tx_dma;
+ gi2c->dma_buf = dma_buf;
}
if (!dma_buf) /* Get FIFO IRQ */
writel_relaxed(1, se->base + SE_GENI_TX_WATERMARK_REG);
+ cur = gi2c->cur;
time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
if (!time_left)
geni_i2c_abort_xfer(gi2c);
- gi2c->cur_wr = 0;
- if (dma_buf) {
- if (gi2c->err)
- geni_i2c_tx_fsm_rst(gi2c);
- geni_se_tx_dma_unprep(se, tx_dma, len);
- i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err);
- }
+ geni_i2c_tx_msg_cleanup(gi2c, cur);
return gi2c->err;
}
--
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