Re: [PATCH v2 4/6] clk: stm32f4: Add RTC clock

From: Stephen Boyd
Date: Wed Oct 19 2016 - 16:46:01 EST


On 10/14, gabriel.fernandez@xxxxxx wrote:
> @@ -310,6 +310,15 @@ static inline void enable_power_domain_write_protection(void)
> regmap_update_bits(pdrm, 0x00, (1 << 8), (0 << 8));
> }
>
> +static inline void sofware_reset_backup_domain(void)
> +{
> + unsigned long val;
> +
> + val = readl(base + STM32F4_RCC_BDCR);
> + writel(val |= (1 << 16), base + STM32F4_RCC_BDCR);

Interesting C style here! Why set the bit in val that will then
be cleared in the next function call? Please just don't do it. It
would be better to do writel(val | BIT(16), ...)

> + writel(val & ~(1 << 16), base + STM32F4_RCC_BDCR);
> +}
> +
> struct stm32_rgate {
> struct clk_hw hw;
> struct clk_gate gate;
> @@ -396,6 +405,113 @@ static struct clk_hw *clk_register_rgate(struct device *dev, const char *name,
> return hw;
> }
>
> +static int cclk_gate_enable(struct clk_hw *hw)
> +{
> + int ret;
> +
> + disable_power_domain_write_protection();
> +
> + ret = clk_gate_ops.enable(hw);
> +
> + enable_power_domain_write_protection();
> +
> + return ret;
> +}
> +
> +static void cclk_gate_disable(struct clk_hw *hw)
> +{
> + disable_power_domain_write_protection();
> +
> + clk_gate_ops.disable(hw);
> +
> + enable_power_domain_write_protection();
> +}
> +
> +static int cclk_gate_is_enabled(struct clk_hw *hw)
> +{
> + return clk_gate_ops.is_enabled(hw);
> +}
> +
> +static const struct clk_ops cclk_gate_ops = {
> + .enable = cclk_gate_enable,
> + .disable = cclk_gate_disable,
> + .is_enabled = cclk_gate_is_enabled,
> +};
> +
> +static u8 cclk_mux_get_parent(struct clk_hw *hw)
> +{
> + return clk_mux_ops.get_parent(hw);
> +}
> +
> +

Weird double newline here. Please remove one.

> +static int cclk_mux_set_parent(struct clk_hw *hw, u8 index)
> +{
> + int ret;
> +
> + disable_power_domain_write_protection();
> +
> + sofware_reset_backup_domain();
> +
> + ret = clk_mux_ops.set_parent(hw, index);
> +
> + enable_power_domain_write_protection();
> +
> + return ret;
> +}
> +
> +

Same.

> +static const struct clk_ops cclk_mux_ops = {
> + .get_parent = cclk_mux_get_parent,
> + .set_parent = cclk_mux_set_parent,
> +};
> +
> +static struct clk_hw *stm32_register_cclk(struct device *dev, const char *name,
> + const char * const *parent_names, int num_parents,
> + void __iomem *reg, u8 bit_idx, u8 shift, unsigned long flags,
> + spinlock_t *lock)
> +{
> + struct clk_hw *hw;
> + struct clk_gate *gate;
> + struct clk_mux *mux;
> +
> + gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);

sizeof(*gate) please.

> + if (!gate) {
> + hw = ERR_PTR(-EINVAL);
> + goto fail;
> + }
> +
> + mux = kzalloc(sizeof(struct clk_mux), GFP_KERNEL);

sizeof(*mux) please.

> + if (!mux) {
> + kfree(gate);
> + hw = ERR_PTR(-EINVAL);
> + goto fail;
> + }
> +

--
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