Re: [PATCH V5 4/4] spi: tegra114: add support for TX and RX trimmers

From: Sowjanya Komatineni
Date: Wed May 22 2019 - 21:13:05 EST


Hi Nathan

Thanks for finding it. I missed to set it to master cleanup when I updated the patch.

Will send the patch fixing this.

Thanks

Sowjanya

On 5/22/19 6:02 PM, Nathan Chancellor wrote:
Hi Sowjanya,

On Mon, May 13, 2019 at 10:03:55PM -0700, Sowjanya Komatineni wrote:
Tegra SPI master controller has programmable trimmers to adjust the
data with respect to the clock.

These trimmers are programmed in TX_CLK_TAP_DELAY and RX_CLK_TAP_DELAY
fields of COMMAND2 register.

SPI TX trimmer is to adjust the outgoing data with respect to the
outgoing clock and SPI RX trimmer is to adjust the loopback clock with
respect to the incoming data from the slave device.

These trimmers vary based on trace lengths of the platform design for
each of the slaves on the SPI bus and optimal value programmed is from
the platform validation across PVT.

This patch adds support for configuring TX and RX clock delay trimmers
through the device tree properties.

Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
---
drivers/spi/spi-tegra114.c | 67 ++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 65 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-tegra114.c b/drivers/spi/spi-tegra114.c
index e59ff7c1cee6..253a7f182fc9 100644
--- a/drivers/spi/spi-tegra114.c
+++ b/drivers/spi/spi-tegra114.c
<snip>

+static void tegra_spi_cleanup(struct spi_device *spi)
+{
+ struct tegra_spi_client_data *cdata = spi->controller_data;
+
+ spi->controller_data = NULL;
+ if (spi->dev.of_node)
+ kfree(cdata);
+}
+
This function is not called anywhere and it is marked as static so it
triggers an unused function warning. Was that intentional?

drivers/spi/spi-tegra114.c:938:13: warning: unused function 'tegra_spi_cleanup' [-Wunused-function]
static void tegra_spi_cleanup(struct spi_device *spi)
^
1 warning generated.

Cheers,
Nathan