mfd: rtsx: Add clock divider hook

Add callback function conv_clk_and_div_n to convert between SSC clock
and its divider N.
For rtl8411, the formula to calculate SSC clock divider N is different
with the other card reader models.

Signed-off-by: Wei WANG <wei_wang@realsil.com.cn>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

diff --git a/drivers/mfd/rtl8411.c b/drivers/mfd/rtl8411.c
index 5058ba8..3d3b4ad 100644 (file)
--- a/drivers/mfd/rtl8411.c
+++ b/drivers/mfd/rtl8411.c
@@ -178,6 +178,18 @@ static unsigned int rtl8411_cd_deglitch(struct rtsx_pcr *pcr)
        return card_exist;
 }
 
+static int rtl8411_conv_clk_and_div_n(int input, int dir)
+{
+       int output;
+
+       if (dir == CLK_TO_DIV_N)
+               output = input * 4 / 5 - 2;
+       else
+               output = (input + 2) * 5 / 4;
+
+       return output;
+}
+
 static const struct pcr_ops rtl8411_pcr_ops = {
        .extra_init_hw = rtl8411_extra_init_hw,
        .optimize_phy = NULL,
@@ -189,6 +201,7 @@ static const struct pcr_ops rtl8411_pcr_ops = {
        .card_power_off = rtl8411_card_power_off,
        .switch_output_voltage = rtl8411_switch_output_voltage,
        .cd_deglitch = rtl8411_cd_deglitch,
+       .conv_clk_and_div_n = rtl8411_conv_clk_and_div_n,
 };
 
 /* SD Pull Control Enable:

diff --git a/drivers/mfd/rts5209.c b/drivers/mfd/rts5209.c
index ba74de8..98fe0f3 100644 (file)
--- a/drivers/mfd/rts5209.c
+++ b/drivers/mfd/rts5209.c
@@ -174,6 +174,7 @@ static const struct pcr_ops rts5209_pcr_ops = {
        .card_power_off = rts5209_card_power_off,
        .switch_output_voltage = rts5209_switch_output_voltage,
        .cd_deglitch = NULL,
+       .conv_clk_and_div_n = NULL,
 };
 
 /* SD Pull Control Enable:

diff --git a/drivers/mfd/rts5229.c b/drivers/mfd/rts5229.c
index ec1747a..29d889c 100644 (file)
--- a/drivers/mfd/rts5229.c
+++ b/drivers/mfd/rts5229.c
@@ -144,6 +144,7 @@ static const struct pcr_ops rts5229_pcr_ops = {
        .card_power_off = rts5229_card_power_off,
        .switch_output_voltage = rts5229_switch_output_voltage,
        .cd_deglitch = NULL,
+       .conv_clk_and_div_n = NULL,
 };
 
 /* SD Pull Control Enable:

diff --git a/drivers/mfd/rtsx_pcr.c b/drivers/mfd/rtsx_pcr.c
index f4e02d0..910200e 100644 (file)
--- a/drivers/mfd/rtsx_pcr.c
+++ b/drivers/mfd/rtsx_pcr.c
@@ -630,7 +630,10 @@ int rtsx_pci_switch_clock(struct rtsx_pcr *pcr, unsigned int card_clock,
        if (clk == pcr->cur_clock)
                return 0;
 
-       N = (u8)(clk - 2);
+       if (pcr->ops->conv_clk_and_div_n)
+               N = (u8)pcr->ops->conv_clk_and_div_n(clk, CLK_TO_DIV_N);
+       else
+               N = (u8)(clk - 2);
        if ((clk <= 2) || (N > max_N))
                return -EINVAL;
 
@@ -641,7 +644,14 @@ int rtsx_pci_switch_clock(struct rtsx_pcr *pcr, unsigned int card_clock,
        /* Make sure that the SSC clock div_n is equal or greater than min_N */
        div = CLK_DIV_1;
        while ((N < min_N) && (div < max_div)) {
-               N = (N + 2) * 2 - 2;
+               if (pcr->ops->conv_clk_and_div_n) {
+                       int dbl_clk = pcr->ops->conv_clk_and_div_n(N,
+                                       DIV_N_TO_CLK) * 2;
+                       N = (u8)pcr->ops->conv_clk_and_div_n(dbl_clk,
+                                       CLK_TO_DIV_N);
+               } else {
+                       N = (N + 2) * 2 - 2;
+               }
                div++;
        }
        dev_dbg(&(pcr->pci->dev), "N = %d, div = %d\n", N, div);

diff --git a/include/linux/mfd/rtsx_common.h b/include/linux/mfd/rtsx_common.h
index a8d393e..2b13970 100644 (file)
--- a/include/linux/mfd/rtsx_common.h
+++ b/include/linux/mfd/rtsx_common.h
@@ -38,6 +38,9 @@
 #define RTSX_SD_CARD                   0
 #define RTSX_MS_CARD                   1
 
+#define CLK_TO_DIV_N                   0
+#define DIV_N_TO_CLK                   1
+
 struct platform_device;
 
 struct rtsx_slot {

diff --git a/include/linux/mfd/rtsx_pci.h b/include/linux/mfd/rtsx_pci.h
index 271b6e5..4b117a3 100644 (file)
--- a/include/linux/mfd/rtsx_pci.h
+++ b/include/linux/mfd/rtsx_pci.h
@@ -704,6 +704,7 @@ struct pcr_ops {
        int             (*switch_output_voltage)(struct rtsx_pcr *pcr,
                                                u8 voltage);
        unsigned int    (*cd_deglitch)(struct rtsx_pcr *pcr);
+       int             (*conv_clk_and_div_n)(int clk, int dir);
 };
 
 enum PDEV_STAT  {PDEV_STAT_IDLE, PDEV_STAT_RUN};