Skip to contentSkip to conversation

clk: aspeed: Handle inverse polarity of USB port 1 clock gate

PATCH Applied Benjamin Herrenschmidt 3 participants 3 messages Jan 12, 2018 – Jan 27, 2018

Subsystems (2)
lore
Share & tools
lore
#0 lore raw

PATCH 1/1 clk: aspeed: Handle inverse polarity of USB port 1 clock gate

The USB port 1 clock gate control has an inversed polarity from all the other clock gates in the chip. This makes the aspeed_clk_{enable,disable} functions honor the flag CLK_GATE_SET_TO_DISABLE and set that flag appropriately so it's set for all clocks except USB port 1.

--

I chose not to add a column to the table for that one special case. If future chips start growing more of these, we should consider adding this to the table instead.

Without this, USB port 1 doesn't work properly with the new clk driver.

---
 drivers/clk/clk-aspeed.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)
drivers/clk/clk-aspeed.c +12 -3
index 6fb344730cea..f5dc5101174e 100644
@@ -211,6 +211,7 @@ static int aspeed_clk_enable(struct clk_hw *hw)
 	unsigned long flags;
 	u32 clk = BIT(gate->clock_idx);
 	u32 rst = BIT(gate->reset_idx);
+	u32 enval;
 
 	spin_lock_irqsave(gate->lock, flags);
 
@@ -223,7 +224,8 @@ static int aspeed_clk_enable(struct clk_hw *hw)
 	}
 
 	/* Enable clock */
-	regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, 0);
+	enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk;
+	regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
 
 	if (gate->reset_idx >= 0) {
 		/* A delay of 10ms is specified by the ASPEED docs */
@@ -243,10 +245,12 @@ static void aspeed_clk_disable(struct clk_hw *hw)
 	struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
 	unsigned long flags;
 	u32 clk = BIT(gate->clock_idx);
+	u32 enval;
 
 	spin_lock_irqsave(gate->lock, flags);
 
-	regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, clk);
+	enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? clk : 0;
+	regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
 
 	spin_unlock_irqrestore(gate->lock, flags);
 }
@@ -478,7 +482,12 @@ static int aspeed_clk_probe(struct platform_device *pdev)
 
 	for (i = 0; i < ARRAY_SIZE(aspeed_gates); i++) {
 		const struct aspeed_gate_data *gd = &aspeed_gates[i];
+		u32 gate_flags;
 
+		/* Special case: the USB port 1 clock (bit 14) is always
+		 * working the opposite way from the other ones.
+		 */
+		gate_flags = (gd->clock_idx == 14) ? 0 : CLK_GATE_SET_TO_DISABLE;
 		hw = aspeed_clk_hw_register_gate(dev,
 				gd->name,
 				gd->parent_name,
@@ -486,7 +495,7 @@ static int aspeed_clk_probe(struct platform_device *pdev)
 				map,
 				gd->clock_idx,
 				gd->reset_idx,
-				CLK_GATE_SET_TO_DISABLE,
+				gate_flags,
 				&aspeed_clk_lock);
 		if (IS_ERR(hw))
 			return PTR_ERR(hw);
maintainer Reviewed-by on v1 1/1
#1 lore raw
Quoted 7 lines · Benjamin Herrenschmidt

The USB port 1 clock gate control has an inversed polarity from all the other clock gates in the chip. This makes the aspeed_clk_{enable,disable} functions honor the flag CLK_GATE_SET_TO_DISABLE and set that flag appropriately so it's set for all clocks except USB port 1.

Quoted 8 lines

--

I chose not to add a column to the table for that one special case. If future chips start growing more of these, we should consider adding this to the table instead.

Without this, USB port 1 doesn't work properly with the new clk driver.

Looks good. I gave this a spin on the ast2500 and the existing functionality worked fine. I don't have local access to test USB at the moment.

Cheers,

Joel

Quoted 65 lines
---
 drivers/clk/clk-aspeed.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)
drivers/clk/clk-aspeed.c +12 -3
index 6fb344730cea..f5dc5101174e 100644
@@ -211,6 +211,7 @@ static int aspeed_clk_enable(struct clk_hw *hw)
        unsigned long flags;
        u32 clk = BIT(gate->clock_idx);
        u32 rst = BIT(gate->reset_idx);
+       u32 enval;
 
        spin_lock_irqsave(gate->lock, flags);
 
@@ -223,7 +224,8 @@ static int aspeed_clk_enable(struct clk_hw *hw)
        }
 
        /* Enable clock */
-       regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, 0);
+       enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk;
+       regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
 
        if (gate->reset_idx >= 0) {
                /* A delay of 10ms is specified by the ASPEED docs */
@@ -243,10 +245,12 @@ static void aspeed_clk_disable(struct clk_hw *hw)
        struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
        unsigned long flags;
        u32 clk = BIT(gate->clock_idx);
+       u32 enval;
 
        spin_lock_irqsave(gate->lock, flags);
 
-       regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, clk);
+       enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? clk : 0;
+       regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
 
        spin_unlock_irqrestore(gate->lock, flags);
 }
@@ -478,7 +482,12 @@ static int aspeed_clk_probe(struct platform_device *pdev)
 
        for (i = 0; i < ARRAY_SIZE(aspeed_gates); i++) {
                const struct aspeed_gate_data *gd = &aspeed_gates[i];
+               u32 gate_flags;
 
+               /* Special case: the USB port 1 clock (bit 14) is always
+                * working the opposite way from the other ones.
+                */
+               gate_flags = (gd->clock_idx == 14) ? 0 : CLK_GATE_SET_TO_DISABLE;
                hw = aspeed_clk_hw_register_gate(dev,
                                gd->name,
                                gd->parent_name,
@@ -486,7 +495,7 @@ static int aspeed_clk_probe(struct platform_device *pdev)
                                map,
                                gd->clock_idx,
                                gd->reset_idx,
-                               CLK_GATE_SET_TO_DISABLE,
+                               gate_flags,
                                &aspeed_clk_lock);
                if (IS_ERR(hw))
                        return PTR_ERR(hw);
Applied
#2 lore raw
In reply to Benjamin Herrenschmidt
Quoted 9 lines · Benjamin Herrenschmidt

The USB port 1 clock gate control has an inversed polarity from all the other clock gates in the chip. This makes the aspeed_clk_{enable,disable} functions honor the flag CLK_GATE_SET_TO_DISABLE and set that flag appropriately so it's set for all clocks except USB port 1.

--

Quoted 8 lines

I chose not to add a column to the table for that one special case. If future chips start growing more of these, we should consider adding this to the table instead.

Without this, USB port 1 doesn't work properly with the new clk driver.

---

Applied to clk-next

Signature · 2 lines
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project