spi: loopback-test: fix potential integer overflow on multiple

[linux-2.6-microblaze.git] / drivers / spi / spi-imx.c

diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index deb782f..32ced64 100644 (file)
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -173,15 +173,16 @@ static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 
 /* MX21, MX27 */
 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
-               unsigned int fspi, unsigned int max)
+               unsigned int fspi, unsigned int max, unsigned int *fres)
 {
        int i;
 
        for (i = 2; i < max; i++)
                if (fspi * mxc_clkdivs[i] >= fin)
-                       return i;
+                       break;
 
-       return max;
+       *fres = fin / mxc_clkdivs[i];
+       return i;
 }
 
 /* MX1, MX31, MX35, MX51 CSPI */
@@ -442,6 +443,7 @@ static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 #define MX31_CSPICTRL_ENABLE   (1 << 0)
 #define MX31_CSPICTRL_MASTER   (1 << 1)
 #define MX31_CSPICTRL_XCH      (1 << 2)
+#define MX31_CSPICTRL_SMC      (1 << 3)
 #define MX31_CSPICTRL_POL      (1 << 4)
 #define MX31_CSPICTRL_PHA      (1 << 5)
 #define MX31_CSPICTRL_SSCTL    (1 << 6)
@@ -452,6 +454,10 @@ static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
 #define MX35_CSPICTRL_CS_SHIFT 12
 #define MX31_CSPICTRL_DR_SHIFT 16
 
+#define MX31_CSPI_DMAREG       0x10
+#define MX31_DMAREG_RH_DEN     (1<<4)
+#define MX31_DMAREG_TH_DEN     (1<<1)
+
 #define MX31_CSPISTATUS                0x14
 #define MX31_STATUS_RR         (1 << 3)
 
@@ -511,6 +517,9 @@ static int mx31_config(struct spi_device *spi, struct spi_imx_config *config)
                        (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
                                                  MX31_CSPICTRL_CS_SHIFT);
 
+       if (spi_imx->usedma)
+               reg |= MX31_CSPICTRL_SMC;
+
        writel(reg, spi_imx->base + MXC_CSPICTRL);
 
        reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
@@ -520,6 +529,13 @@ static int mx31_config(struct spi_device *spi, struct spi_imx_config *config)
                reg &= ~MX31_TEST_LBC;
        writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
 
+       if (spi_imx->usedma) {
+               /* configure DMA requests when RXFIFO is half full and
+                  when TXFIFO is half empty */
+               writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
+                       spi_imx->base + MX31_CSPI_DMAREG);
+       }
+
        return 0;
 }
 
@@ -574,9 +590,12 @@ static int mx21_config(struct spi_device *spi, struct spi_imx_config *config)
        struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
        unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
        unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
+       unsigned int clk;
+
+       reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max, &clk)
+               << MX21_CSPICTRL_DR_SHIFT;
+       spi_imx->spi_bus_clk = clk;
 
-       reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) <<
-               MX21_CSPICTRL_DR_SHIFT;
        reg |= config->bpw - 1;
 
        if (spi->mode & SPI_CPHA)
@@ -1244,10 +1263,10 @@ static int spi_imx_probe(struct platform_device *pdev)
 
        spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
        /*
-        * Only validated on i.mx6 now, can remove the constrain if validated on
-        * other chips.
+        * Only validated on i.mx35 and i.mx6 now, can remove the constraint
+        * if validated on other chips.
         */
-       if (is_imx51_ecspi(spi_imx)) {
+       if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx)) {
                ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
                if (ret == -EPROBE_DEFER)
                        goto out_clk_put;