[PATCH] spi: mtk_spim: prevent global pll clock override

[Nicolò Veronese]

With commit 793e6230118032a099ec42a1ea67f434721edcc0
 a new system to calculate the SPI clocks has been added.

Unfortunately, the do_div macro overrides the global
 priv->pll_clk_rate field. This will cause to have a reduced
 clock rate on each subsequent SPI call.

Signed-off-by: Valerio 'ftp21' Mancini <ftp21 at ftp21.eu>
Signed-off-by: Nicolò Veronese <nicveronese at gmail.com>
---
 drivers/spi/mtk_spim.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/spi/mtk_spim.c b/drivers/spi/mtk_spim.c
index 418e586b91..90f4c3cecb 100644
--- a/drivers/spi/mtk_spim.c
+++ b/drivers/spi/mtk_spim.c
@@ -409,7 +409,7 @@ static int mtk_spim_transfer_wait(struct spi_slave *slave,
 {
     struct udevice *bus = dev_get_parent(slave->dev);
     struct mtk_spim_priv *priv = dev_get_priv(bus);
-    u32 sck_l, sck_h, clk_count, reg;
+    u32 pll_clk, sck_l, sck_h, clk_count, reg;
     ulong us = 1;
     int ret = 0;

@@ -418,11 +418,12 @@ static int mtk_spim_transfer_wait(struct spi_slave *slave,
     else
         clk_count = op->data.nbytes;

+    pll_clk = priv->pll_clk_rate;
     sck_l = readl(priv->base + SPI_CFG2_REG) >> SPI_CFG2_SCK_LOW_OFFSET;
     sck_h = readl(priv->base + SPI_CFG2_REG) & SPI_CFG2_SCK_HIGH_MASK;
-    do_div(priv->pll_clk_rate, sck_l + sck_h + 2);
+    do_div(pll_clk, sck_l + sck_h + 2);

-    us = CLK_TO_US(priv->pll_clk_rate, clk_count * 8);
+    us = CLK_TO_US(pll_clk, clk_count * 8);
     us += 1000 * 1000; /* 1s tolerance */

     if (us > UINT_MAX)
-- 
2.30.2