Messages in this thread Patch in this message | | | Date | Fri, 15 May 2020 16:03:05 +0300 | From | Andy Shevchenko <> | Subject | Re: [PATCH v2 08/19] spi: dw: Discard dma_width member of the dw_spi structure |
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On Fri, May 15, 2020 at 01:47:47PM +0300, Serge Semin wrote: > This member has exactly the same value as n_bytes of the DW SPI private > data object, it's calculated at the same point of the transfer method, > n_bytes isn't changed during the whole transfer, and they even serve for > the same purpose - keep number of bytes per transfer word, though the > dma_width is used only to calculate the DMA source/destination addresses > width, which n_bytes could be also utilized for. Taking all of these > into account let's replace the dma_width member usage with n_bytes one > and remove the former.
I've no strong opinion about this. So, after addressing one issue below, Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> 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: Paul Burton <paulburton@kernel.org> > Cc: Ralf Baechle <ralf@linux-mips.org> > Cc: Allison Randal <allison@lohutok.net> > Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Cc: Gareth Williams <gareth.williams.jx@renesas.com> > Cc: Arnd Bergmann <arnd@arndb.de> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: linux-mips@vger.kernel.org > Cc: devicetree@vger.kernel.org > > --- > > Changelog v2: > - It's a new patch created as a result of more thorough driver study. > --- > drivers/spi/spi-dw-mid.c | 10 +++++----- > drivers/spi/spi-dw.c | 1 - > drivers/spi/spi-dw.h | 1 - > 3 files changed, 5 insertions(+), 7 deletions(-) > > diff --git a/drivers/spi/spi-dw-mid.c b/drivers/spi/spi-dw-mid.c > index be886e22a1b1..ca8813a693d8 100644 > --- a/drivers/spi/spi-dw-mid.c > +++ b/drivers/spi/spi-dw-mid.c > @@ -132,10 +132,10 @@ static bool mid_spi_can_dma(struct spi_controller *master, > return xfer->len > dws->fifo_len; > } > > -static enum dma_slave_buswidth convert_dma_width(u32 dma_width) { > - if (dma_width == 1)
> +static enum dma_slave_buswidth convert_dma_width(u8 n_bytes) {
It seems somebody (maybe even me) at some point messed up between enum definition and function that returns an enum.
For what said, { should be on the separate line.
> + if (n_bytes == 1) > return DMA_SLAVE_BUSWIDTH_1_BYTE; > - else if (dma_width == 2) > + else if (n_bytes == 2) > return DMA_SLAVE_BUSWIDTH_2_BYTES; > > return DMA_SLAVE_BUSWIDTH_UNDEFINED; > @@ -195,7 +195,7 @@ static struct dma_async_tx_descriptor *dw_spi_dma_prepare_tx(struct dw_spi *dws, > txconf.dst_addr = dws->dma_addr; > txconf.dst_maxburst = 16; > txconf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; > - txconf.dst_addr_width = convert_dma_width(dws->dma_width); > + txconf.dst_addr_width = convert_dma_width(dws->n_bytes); > txconf.device_fc = false; > > dmaengine_slave_config(dws->txchan, &txconf); > @@ -268,7 +268,7 @@ static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws, > rxconf.src_addr = dws->dma_addr; > rxconf.src_maxburst = 16; > rxconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; > - rxconf.src_addr_width = convert_dma_width(dws->dma_width); > + rxconf.src_addr_width = convert_dma_width(dws->n_bytes); > rxconf.device_fc = false; > > dmaengine_slave_config(dws->rxchan, &rxconf); > diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c > index 450c8218caeb..1edb8cdd11ee 100644 > --- a/drivers/spi/spi-dw.c > +++ b/drivers/spi/spi-dw.c > @@ -353,7 +353,6 @@ static int dw_spi_transfer_one(struct spi_controller *master, > } > > dws->n_bytes = DIV_ROUND_UP(transfer->bits_per_word, BITS_PER_BYTE); > - dws->dma_width = DIV_ROUND_UP(transfer->bits_per_word, BITS_PER_BYTE); > > cr0 = dws->update_cr0(master, spi, transfer); > dw_writel(dws, DW_SPI_CTRLR0, cr0); > diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h > index b6ab81e0c747..4902f937c3d7 100644 > --- a/drivers/spi/spi-dw.h > +++ b/drivers/spi/spi-dw.h > @@ -136,7 +136,6 @@ struct dw_spi { > void *rx_end; > int dma_mapped; > u8 n_bytes; /* current is a 1/2 bytes op */ > - u32 dma_width; > irqreturn_t (*transfer_handler)(struct dw_spi *dws); > u32 current_freq; /* frequency in hz */ > > -- > 2.25.1 >
-- With Best Regards, Andy Shevchenko
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