Commit 72a85e2b authored by Linus Torvalds's avatar Linus Torvalds

Merge tag 'spi-fix-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi fix from Mark Brown:
 "One driver specific change here which handles the case where a SPI
  device for some reason tries to change the bus speed during a message
  on fsl_spi hardware, this should be very unusual"

* tag 'spi-fix-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: fsl_spi: Don't change speed while chipselect is active
parents 0a023cbb 3b553e00
...@@ -333,13 +333,26 @@ static int fsl_spi_prepare_message(struct spi_controller *ctlr, ...@@ -333,13 +333,26 @@ static int fsl_spi_prepare_message(struct spi_controller *ctlr,
{ {
struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(ctlr); struct mpc8xxx_spi *mpc8xxx_spi = spi_controller_get_devdata(ctlr);
struct spi_transfer *t; struct spi_transfer *t;
struct spi_transfer *first;
first = list_first_entry(&m->transfers, struct spi_transfer,
transfer_list);
/* /*
* In CPU mode, optimize large byte transfers to use larger * In CPU mode, optimize large byte transfers to use larger
* bits_per_word values to reduce number of interrupts taken. * bits_per_word values to reduce number of interrupts taken.
*
* Some glitches can appear on the SPI clock when the mode changes.
* Check that there is no speed change during the transfer and set it up
* now to change the mode without having a chip-select asserted.
*/ */
if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) {
list_for_each_entry(t, &m->transfers, transfer_list) { list_for_each_entry(t, &m->transfers, transfer_list) {
if (t->speed_hz != first->speed_hz) {
dev_err(&m->spi->dev,
"speed_hz cannot change during message.\n");
return -EINVAL;
}
if (!(mpc8xxx_spi->flags & SPI_CPM_MODE)) {
if (t->len < 256 || t->bits_per_word != 8) if (t->len < 256 || t->bits_per_word != 8)
continue; continue;
if ((t->len & 3) == 0) if ((t->len & 3) == 0)
...@@ -348,7 +361,7 @@ static int fsl_spi_prepare_message(struct spi_controller *ctlr, ...@@ -348,7 +361,7 @@ static int fsl_spi_prepare_message(struct spi_controller *ctlr,
t->bits_per_word = 16; t->bits_per_word = 16;
} }
} }
return 0; return fsl_spi_setup_transfer(m->spi, first);
} }
static int fsl_spi_transfer_one(struct spi_controller *controller, static int fsl_spi_transfer_one(struct spi_controller *controller,
......
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