| Message ID | 20200529131205.31838-2-Sergey.Semin@baikalelectronics.ru (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | spi: dw: Add generic DW DMA controller support | expand |
diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c index 9d6904d30104..050cb2ea0812 100644 --- a/drivers/spi/spi-dw.c +++ b/drivers/spi/spi-dw.c @@ -352,6 +352,7 @@ static int dw_spi_transfer_one(struct spi_controller *master, spi_set_clk(dws, chip->clk_div); } + transfer->effective_speed_hz = dws->max_freq / chip->clk_div; dws->n_bytes = DIV_ROUND_UP(transfer->bits_per_word, BITS_PER_BYTE); cr0 = dws->update_cr0(master, spi, transfer);
Seeing DW APB SSI controller doesn't support setting the exactly requested SPI bus frequency, but only a rounded frequency determined by means of the odd-numbered half-worded reference clock divider, it would be good to tune the SPI core up and initialize the current transfer effective_speed_hz. By doing so the core will be able to execute the xfer-related delays with better accuracy. Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru> Cc: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru> Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru> Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Feng Tang <feng.tang@intel.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rob Herring <robh+dt@kernel.org> Cc: linux-mips@vger.kernel.org Cc: devicetree@vger.kernel.org --- drivers/spi/spi-dw.c | 1 + 1 file changed, 1 insertion(+)