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authorMauro Carvalho Chehab <mchehab+huawei@kernel.org>2021-08-05 16:28:43 +0200
committerMauro Carvalho Chehab <mchehab+huawei@kernel.org>2021-08-05 16:28:43 +0200
commit9c3a0f285248899dfa81585bc5d5bc9ebdb8fead (patch)
tree908decd51fbb0e1c774444b002e3b89dee3fae26 /drivers/spi/spi-imx.c
parentbfee75f73c37a2f46a6326eaa06f5db701f76f01 (diff)
parentc500bee1c5b2f1d59b1081ac879d73268ab0ff17 (diff)
Merge tag 'v5.14-rc4' into media_tree
Linux 5.14-rc4 * tag 'v5.14-rc4': (948 commits) Linux 5.14-rc4 pipe: make pipe writes always wake up readers Revert "perf map: Fix dso->nsinfo refcounting" mm/memcg: fix NULL pointer dereference in memcg_slab_free_hook() slub: fix unreclaimable slab stat for bulk free mm/migrate: fix NR_ISOLATED corruption on 64-bit mm: memcontrol: fix blocking rstat function called from atomic cgroup1 thresholding code ocfs2: issue zeroout to EOF blocks ocfs2: fix zero out valid data lib/test_string.c: move string selftest in the Runtime Testing menu gve: Update MAINTAINERS list arch: Kconfig: clean up obsolete use of HAVE_IDE can: esd_usb2: fix memory leak can: ems_usb: fix memory leak can: usb_8dev: fix memory leak can: mcba_usb_start(): add missing urb->transfer_dma initialization can: hi311x: fix a signedness bug in hi3110_cmd() MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS Analyzer Tool driver scsi: fas216: Fix fall-through warning for Clang scsi: acornscsi: Fix fall-through warning for clang ...
Diffstat (limited to 'drivers/spi/spi-imx.c')
-rw-r--r--drivers/spi/spi-imx.c38
1 files changed, 19 insertions, 19 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index 39dc02e366f4..4aee3db6d6df 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -506,7 +506,7 @@ static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
{
struct spi_device *spi = msg->spi;
u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
- u32 testreg;
+ u32 testreg, delay;
u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
/* set Master or Slave mode */
@@ -567,6 +567,23 @@ static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
+ /*
+ * Wait until the changes in the configuration register CONFIGREG
+ * propagate into the hardware. It takes exactly one tick of the
+ * SCLK clock, but we will wait two SCLK clock just to be sure. The
+ * effect of the delay it takes for the hardware to apply changes
+ * is noticable if the SCLK clock run very slow. In such a case, if
+ * the polarity of SCLK should be inverted, the GPIO ChipSelect might
+ * be asserted before the SCLK polarity changes, which would disrupt
+ * the SPI communication as the device on the other end would consider
+ * the change of SCLK polarity as a clock tick already.
+ */
+ delay = (2 * 1000000) / spi_imx->spi_bus_clk;
+ if (likely(delay < 10)) /* SCLK is faster than 100 kHz */
+ udelay(delay);
+ else /* SCLK is _very_ slow */
+ usleep_range(delay, delay + 10);
+
return 0;
}
@@ -574,7 +591,7 @@ static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
struct spi_device *spi)
{
u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
- u32 clk, delay;
+ u32 clk;
/* Clear BL field and set the right value */
ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
@@ -596,23 +613,6 @@ static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
- /*
- * Wait until the changes in the configuration register CONFIGREG
- * propagate into the hardware. It takes exactly one tick of the
- * SCLK clock, but we will wait two SCLK clock just to be sure. The
- * effect of the delay it takes for the hardware to apply changes
- * is noticable if the SCLK clock run very slow. In such a case, if
- * the polarity of SCLK should be inverted, the GPIO ChipSelect might
- * be asserted before the SCLK polarity changes, which would disrupt
- * the SPI communication as the device on the other end would consider
- * the change of SCLK polarity as a clock tick already.
- */
- delay = (2 * 1000000) / clk;
- if (likely(delay < 10)) /* SCLK is faster than 100 kHz */
- udelay(delay);
- else /* SCLK is _very_ slow */
- usleep_range(delay, delay + 10);
-
return 0;
}