2 files changed, 113 insertions, 18 deletions

diff --git a/Documentation/devicetree/bindings/clock/renesas,cpg-div6-clocks.txt b/Documentation/devicetree/bindings/clock/renesas,cpg-div6-clocks.txt
index 952e373178d2..054f65f9319c 100644
--- a/Documentation/devicetree/bindings/clock/renesas,cpg-div6-clocks.txt
+++ b/Documentation/devicetree/bindings/clock/renesas,cpg-div6-clocks.txt
@@ -7,11 +7,16 @@ to 64.
 Required Properties:
 
   - compatible: Must be one of the following
+    - "renesas,r8a73a4-div6-clock" for R8A73A4 (R-Mobile APE6) DIV6 clocks
+    - "renesas,r8a7740-div6-clock" for R8A7740 (R-Mobile A1) DIV6 clocks
     - "renesas,r8a7790-div6-clock" for R8A7790 (R-Car H2) DIV6 clocks
     - "renesas,r8a7791-div6-clock" for R8A7791 (R-Car M2) DIV6 clocks
+    - "renesas,sh73a0-div6-clock" for SH73A0 (SH-Mobile AG5) DIV6 clocks
     - "renesas,cpg-div6-clock" for generic DIV6 clocks
   - reg: Base address and length of the memory resource used by the DIV6 clock
-  - clocks: Reference to the parent clock
+  - clocks: Reference to the parent clock(s); either one, four, or eight
+    clocks must be specified.  For clocks with multiple parents, invalid
+    settings must be specified as "<0>".
   - #clock-cells: Must be 0
   - clock-output-names: The name of the clock as a free-form string
 
@@ -19,10 +24,11 @@ Required Properties:
 Example
 -------
 
-        sd2_clk: sd2_clk@e6150078 {
-                compatible = "renesas,r8a7790-div6-clock", "renesas,cpg-div6-clock";
-                reg = <0 0xe6150078 0 4>;
-                clocks = <&pll1_div2_clk>;
+        sdhi2_clk: sdhi2_clk@e615007c {
+                compatible = "renesas,r8a73a4-div6-clock", "renesas,cpg-div6-clock";
+                reg = <0 0xe615007c 0 4>;
+                clocks = <&pll1_div2_clk>, <&cpg_clocks R8A73A4_CLK_PLL2S>,
+                         <0>, <&extal2_clk>;
                 #clock-cells = <0>;
-                clock-output-names = "sd2";
+                clock-output-names = "sdhi2ck";
         };
diff --git a/drivers/clk/shmobile/clk-div6.c b/drivers/clk/shmobile/clk-div6.c
index f065f694cb65..639241e31e03 100644
--- a/drivers/clk/shmobile/clk-div6.c
+++ b/drivers/clk/shmobile/clk-div6.c
@@ -32,6 +32,9 @@ struct div6_clock {
         struct clk_hw hw;
         void __iomem *reg;
         unsigned int div;
+        u32 src_shift;
+        u32 src_width;
+        u8 *parents;
 };
 
 #define to_div6_clock(_hw) container_of(_hw, struct div6_clock, hw)
@@ -39,8 +42,11 @@ struct div6_clock {
 static int cpg_div6_clock_enable(struct clk_hw *hw)
 {
         struct div6_clock *clock = to_div6_clock(hw);
+        u32 val;
 
-        clk_writel(CPG_DIV6_DIV(clock->div - 1), clock->reg);
+        val = (clk_readl(clock->reg) & ~(CPG_DIV6_DIV_MASK | CPG_DIV6_CKSTP))
+            | CPG_DIV6_DIV(clock->div - 1);
+        clk_writel(val, clock->reg);
 
         return 0;
 }
@@ -52,7 +58,7 @@ static void cpg_div6_clock_disable(struct clk_hw *hw)
         /* DIV6 clocks require the divisor field to be non-zero when stopping
          * the clock.
          */
-        clk_writel(CPG_DIV6_CKSTP | CPG_DIV6_DIV(CPG_DIV6_DIV_MASK),
+        clk_writel(clk_readl(clock->reg) | CPG_DIV6_CKSTP | CPG_DIV6_DIV_MASK,
                    clock->reg);
 }
 
@@ -94,12 +100,53 @@ static int cpg_div6_clock_set_rate(struct clk_hw *hw, unsigned long rate,
 {
         struct div6_clock *clock = to_div6_clock(hw);
         unsigned int div = cpg_div6_clock_calc_div(rate, parent_rate);
+        u32 val;
 
         clock->div = div;
 
+        val = clk_readl(clock->reg) & ~CPG_DIV6_DIV_MASK;
         /* Only program the new divisor if the clock isn't stopped. */
-        if (!(clk_readl(clock->reg) & CPG_DIV6_CKSTP))
-                clk_writel(CPG_DIV6_DIV(clock->div - 1), clock->reg);
+        if (!(val & CPG_DIV6_CKSTP))
+                clk_writel(val | CPG_DIV6_DIV(clock->div - 1), clock->reg);
+
+        return 0;
+}
+
+static u8 cpg_div6_clock_get_parent(struct clk_hw *hw)
+{
+        struct div6_clock *clock = to_div6_clock(hw);
+        unsigned int i;
+        u8 hw_index;
+
+        if (clock->src_width == 0)
+                return 0;
+
+        hw_index = (clk_readl(clock->reg) >> clock->src_shift) &
+                   (BIT(clock->src_width) - 1);
+        for (i = 0; i < __clk_get_num_parents(hw->clk); i++) {
+                if (clock->parents[i] == hw_index)
+                        return i;
+        }
+
+        pr_err("%s: %s DIV6 clock set to invalid parent %u\n",
+               __func__, __clk_get_name(hw->clk), hw_index);
+        return 0;
+}
+
+static int cpg_div6_clock_set_parent(struct clk_hw *hw, u8 index)
+{
+        struct div6_clock *clock = to_div6_clock(hw);
+        u8 hw_index;
+        u32 mask;
+
+        if (index >= __clk_get_num_parents(hw->clk))
+                return -EINVAL;
+
+        mask = ~((BIT(clock->src_width) - 1) << clock->src_shift);
+        hw_index = clock->parents[index];
+
+        clk_writel((clk_readl(clock->reg) & mask) |
+                (hw_index << clock->src_shift), clock->reg);
 
         return 0;
 }
@@ -108,6 +155,8 @@ static const struct clk_ops cpg_div6_clock_ops = {
         .enable = cpg_div6_clock_enable,
         .disable = cpg_div6_clock_disable,
         .is_enabled = cpg_div6_clock_is_enabled,
+        .get_parent = cpg_div6_clock_get_parent,
+        .set_parent = cpg_div6_clock_set_parent,
         .recalc_rate = cpg_div6_clock_recalc_rate,
         .round_rate = cpg_div6_clock_round_rate,
         .set_rate = cpg_div6_clock_set_rate,
@@ -115,20 +164,33 @@ static const struct clk_ops cpg_div6_clock_ops = {
 
 static void __init cpg_div6_clock_init(struct device_node *np)
 {
+        unsigned int num_parents, valid_parents;
+        const char **parent_names;
         struct clk_init_data init;
         struct div6_clock *clock;
-        const char *parent_name;
         const char *name;
         struct clk *clk;
+        unsigned int i;
         int ret;
 
         clock = kzalloc(sizeof(*clock), GFP_KERNEL);
-        if (!clock) {
-                pr_err("%s: failed to allocate %s DIV6 clock\n",
+        if (!clock)
+                return;
+
+        num_parents = of_clk_get_parent_count(np);
+        if (num_parents < 1) {
+                pr_err("%s: no parent found for %s DIV6 clock\n",
                        __func__, np->name);
                 return;
         }
 
+        clock->parents = kmalloc_array(num_parents, sizeof(*clock->parents),
+                GFP_KERNEL);
+        parent_names = kmalloc_array(num_parents, sizeof(*parent_names),
+                                GFP_KERNEL);
+        if (!parent_names)
+                return;
+
         /* Remap the clock register and read the divisor. Disabling the
          * clock overwrites the divisor, so we need to cache its value for the
          * enable operation.
@@ -150,9 +212,34 @@ static void __init cpg_div6_clock_init(struct device_node *np)
                 goto error;
         }
 
-        parent_name = of_clk_get_parent_name(np, 0);
-        if (parent_name == NULL) {
-                pr_err("%s: failed to get %s DIV6 clock parent name\n",
+
+        for (i = 0, valid_parents = 0; i < num_parents; i++) {
+                const char *name = of_clk_get_parent_name(np, i);
+
+                if (name) {
+                        parent_names[valid_parents] = name;
+                        clock->parents[valid_parents] = i;
+                        valid_parents++;
+                }
+        }
+
+        switch (num_parents) {
+        case 1:
+                /* fixed parent clock */
+                clock->src_shift = clock->src_width = 0;
+                break;
+        case 4:
+                /* clock with EXSRC bits 6-7 */
+                clock->src_shift = 6;
+                clock->src_width = 2;
+                break;
+        case 8:
+                /* VCLK with EXSRC bits 12-14 */
+                clock->src_shift = 12;
+                clock->src_width = 3;
+                break;
+        default:
+                pr_err("%s: invalid number of parents for DIV6 clock %s\n",
                        __func__, np->name);
                 goto error;
         }
@@ -161,8 +248,8 @@ static void __init cpg_div6_clock_init(struct device_node *np)
         init.name = name;
         init.ops = &cpg_div6_clock_ops;
         init.flags = CLK_IS_BASIC;
-        init.parent_names = &parent_name;
-        init.num_parents = 1;
+        init.parent_names = parent_names;
+        init.num_parents = valid_parents;
 
         clock->hw.init = &init;
 
@@ -175,11 +262,13 @@ static void __init cpg_div6_clock_init(struct device_node *np)
 
         of_clk_add_provider(np, of_clk_src_simple_get, clk);
 
+        kfree(parent_names);
         return;
 
 error:
         if (clock->reg)
                 iounmap(clock->reg);
+        kfree(parent_names);
         kfree(clock);
 }
 CLK_OF_DECLARE(cpg_div6_clk, "renesas,cpg-div6-clock", cpg_div6_clock_init);