SPI: mxc_spi: delay initialisation until claim bus

it is not correct to init for a specific slave in spi_setup_slave.
instead buffer the values and delay init until spi_claim_bus.

Signed-off-by: Markus Niebel <Markus.Niebel@tq-group.com>
Acked-by: Stefano Babic <sbabic@denx.de>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>

diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c
index 523c7af20466f602e98f7bd106cefc2b846d5b64..23f2ba6223dce6d089ac6af3ac153b19d4e79844 100644 (file)
--- a/drivers/spi/mxc_spi.c
+++ b/drivers/spi/mxc_spi.c
@@ -49,6 +49,8 @@ struct mxc_spi_slave {
 #endif
        int             gpio;
        int             ss_pol;
+       unsigned int    max_hz;
+       unsigned int    mode;
 };
 
 static inline struct mxc_spi_slave *to_mxc_spi_slave(struct spi_slave *slave)
@@ -83,12 +85,13 @@ u32 get_cspi_div(u32 div)
 }
 
 #ifdef MXC_CSPI
-static s32 spi_cfg_mxc(struct mxc_spi_slave *mxcs, unsigned int cs,
-               unsigned int max_hz, unsigned int mode)
+static s32 spi_cfg_mxc(struct mxc_spi_slave *mxcs, unsigned int cs)
 {
        unsigned int ctrl_reg;
        u32 clk_src;
        u32 div;
+       unsigned int max_hz = mxcs->max_hz;
+       unsigned int mode = mxcs->mode;
 
        clk_src = mxc_get_clock(MXC_CSPI_CLK);
 
@@ -120,19 +123,15 @@ static s32 spi_cfg_mxc(struct mxc_spi_slave *mxcs, unsigned int cs,
 #endif
 
 #ifdef MXC_ECSPI
-static s32 spi_cfg_mxc(struct mxc_spi_slave *mxcs, unsigned int cs,
-               unsigned int max_hz, unsigned int mode)
+static s32 spi_cfg_mxc(struct mxc_spi_slave *mxcs, unsigned int cs)
 {
        u32 clk_src = mxc_get_clock(MXC_CSPI_CLK);
        s32 reg_ctrl, reg_config;
        u32 ss_pol = 0, sclkpol = 0, sclkpha = 0, sclkctl = 0;
        u32 pre_div = 0, post_div = 0;
        struct cspi_regs *regs = (struct cspi_regs *)mxcs->base;
-
-       if (max_hz == 0) {
-               printf("Error: desired clock is 0\n");
-               return -1;
-       }
+       unsigned int max_hz = mxcs->max_hz;
+       unsigned int mode = mxcs->mode;
 
        /*
         * Reset SPI and set all CSs to master mode, if toggling
@@ -409,6 +408,11 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
        if (bus >= ARRAY_SIZE(spi_bases))
                return NULL;
 
+       if (max_hz == 0) {
+               printf("Error: desired clock is 0\n");
+               return NULL;
+       }
+
        mxcs = spi_alloc_slave(struct mxc_spi_slave, bus, cs);
        if (!mxcs) {
                puts("mxc_spi: SPI Slave not allocated !\n");
@@ -424,13 +428,9 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
        }
 
        mxcs->base = spi_bases[bus];
+       mxcs->max_hz = max_hz;
+       mxcs->mode = mode;
 
-       ret = spi_cfg_mxc(mxcs, cs, max_hz, mode);
-       if (ret) {
-               printf("mxc_spi: cannot setup SPI controller\n");
-               free(mxcs);
-               return NULL;
-       }
        return &mxcs->slave;
 }
 
@@ -443,12 +443,17 @@ void spi_free_slave(struct spi_slave *slave)
 
 int spi_claim_bus(struct spi_slave *slave)
 {
+       int ret;
        struct mxc_spi_slave *mxcs = to_mxc_spi_slave(slave);
        struct cspi_regs *regs = (struct cspi_regs *)mxcs->base;
 
        reg_write(&regs->rxdata, 1);
        udelay(1);
-       reg_write(&regs->ctrl, mxcs->ctrl_reg);
+       ret = spi_cfg_mxc(mxcs, slave->cs);
+       if (ret) {
+               printf("mxc_spi: cannot setup SPI controller\n");
+               return ret;
+       }
        reg_write(&regs->period, MXC_CSPIPERIOD_32KHZ);
        reg_write(&regs->intr, 0);