From 00f73f97527f6ea8b4bc2bc63c44299bcc2f5cab Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Wed, 10 Oct 2018 15:50:50 -0700 Subject: [PATCH] Input: elants_i2c - use DMA safe i2c when possible To avoid bounce buffer when an i2c controller decides to use DMA for a transaction, let's make out buffer that we use for reads DMA-safe and let the master know that DMAing into it is safe. Signed-off-by: Stephen Boyd Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/elants_i2c.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/input/touchscreen/elants_i2c.c b/drivers/input/touchscreen/elants_i2c.c index d21ca39..f2cb231 100644 --- a/drivers/input/touchscreen/elants_i2c.c +++ b/drivers/input/touchscreen/elants_i2c.c @@ -147,10 +147,11 @@ struct elants_data { u8 cmd_resp[HEADER_SIZE]; struct completion cmd_done; - u8 buf[MAX_PACKET_SIZE]; - bool wake_irq_enabled; bool keep_power_in_suspend; + + /* Must be last to be used for DMA operations */ + u8 buf[MAX_PACKET_SIZE] ____cacheline_aligned; }; static int elants_i2c_send(struct i2c_client *client, @@ -863,7 +864,7 @@ static irqreturn_t elants_i2c_irq(int irq, void *_dev) int i; int len; - len = i2c_master_recv(client, ts->buf, sizeof(ts->buf)); + len = i2c_master_recv_dmasafe(client, ts->buf, sizeof(ts->buf)); if (len < 0) { dev_err(&client->dev, "%s: failed to read data: %d\n", __func__, len); -- 2.7.4