6.12-stable review patch. If anyone has any objections, please let me know.
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From: Christian Loehle christian.loehle@arm.com
commit 0bb394067a792e7119abc9e0b7158ef19381f456 upstream.
The early bail out that caused an out-of-bounds write was removed with commit 5c018e378f91 ("spi: spi-rockchip: Fix out of bounds array access") Unfortunately that caused the PM runtime count to be unbalanced and underflowed on the first call. To fix that reintroduce a no-op check by reading the register directly.
Cc: stable@vger.kernel.org Fixes: 5c018e378f91 ("spi: spi-rockchip: Fix out of bounds array access") Signed-off-by: Christian Loehle christian.loehle@arm.com Link: https://patch.msgid.link/1f2b3af4-2b7a-4ac8-ab95-c80120ebf44c@arm.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/spi/spi-rockchip.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
--- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -241,6 +241,20 @@ static void rockchip_spi_set_cs(struct s struct spi_controller *ctlr = spi->controller; struct rockchip_spi *rs = spi_controller_get_devdata(ctlr); bool cs_asserted = spi->mode & SPI_CS_HIGH ? enable : !enable; + bool cs_actual; + + /* + * SPI subsystem tries to avoid no-op calls that would break the PM + * refcount below. It can't however for the first time it is used. + * To detect this case we read it here and bail out early for no-ops. + */ + if (spi_get_csgpiod(spi, 0)) + cs_actual = !!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SER) & 1); + else + cs_actual = !!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SER) & + BIT(spi_get_chipselect(spi, 0))); + if (unlikely(cs_actual == cs_asserted)) + return;
if (cs_asserted) { /* Keep things powered as long as CS is asserted */