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authorDavid Lechner <dlechner@baylibre.com>2023-12-04 20:33:28 +0300
committerMark Brown <broonie@kernel.org>2023-12-06 17:19:30 +0300
commit9d023ecc31859c7f7c8ca27b5fec52b2dbb8086f (patch)
tree6f3905e804724f952544b02339ea0f78db3496b8
parent2e0d75f8dd9e31b3fb175f780494dd7dd988ceae (diff)
downloadlinux-9d023ecc31859c7f7c8ca27b5fec52b2dbb8086f.tar.xz
spi: axi-spi-engine: populate xfer->effective_speed_hz
This adds a new spi_engine_precompile_message() function to the ADI AXI SPI Engine driver to populate the xfer->effective_speed_hz field since the SPI core doesn't/can't do this for us. This driver is already using spi_delay_to_ns() which depends on effective_speed_hz to get an accurate value in some cases. Having an effective_speed_hz value can also be used in future changes to simplify other code. Signed-off-by: David Lechner <dlechner@baylibre.com> Acked-by: Michael Hennerich <michael.hennerich@analog.com> Acked-by: Nuno Sa <nuno.sa@analog.com> Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-2-063672323fce@baylibre.com Signed-off-by: Mark Brown <broonie@kernel.org>
-rw-r--r--drivers/spi/spi-axi-spi-engine.c23
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi-engine.c
index 982b37ac3063..ee7b904ae5cf 100644
--- a/drivers/spi/spi-axi-spi-engine.c
+++ b/drivers/spi/spi-axi-spi-engine.c
@@ -218,6 +218,27 @@ static void spi_engine_gen_cs(struct spi_engine_program *p, bool dry,
spi_engine_program_add_cmd(p, dry, SPI_ENGINE_CMD_ASSERT(1, mask));
}
+/*
+ * Performs precompile steps on the message.
+ *
+ * The SPI core does most of the message/transfer validation and filling in
+ * fields for us via __spi_validate(). This fixes up anything remaining not
+ * done there.
+ *
+ * NB: This is separate from spi_engine_compile_message() because the latter
+ * is called twice and would otherwise result in double-evaluation.
+ */
+static void spi_engine_precompile_message(struct spi_message *msg)
+{
+ unsigned int clk_div, max_hz = msg->spi->controller->max_speed_hz;
+ struct spi_transfer *xfer;
+
+ list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+ clk_div = DIV_ROUND_UP(max_hz, xfer->speed_hz);
+ xfer->effective_speed_hz = max_hz / min(clk_div, 256U);
+ }
+}
+
static void spi_engine_compile_message(struct spi_engine *spi_engine,
struct spi_message *msg, bool dry, struct spi_engine_program *p)
{
@@ -504,6 +525,8 @@ static int spi_engine_prepare_message(struct spi_controller *host,
if (!st)
return -ENOMEM;
+ spi_engine_precompile_message(msg);
+
p_dry.length = 0;
spi_engine_compile_message(spi_engine, msg, true, &p_dry);