Re: [PATCHv5 01/35] clk: ti: fix ti_clk_get_reg_addr error handling

[Tero Kristo <t-kristo@ti.com>]

On 03/20/2015 08:44 PM, Tero Kristo wrote:
> There is a case where NULL can be a valid return value for
> ti_clk_get_reg_addr, specifically the case where both the provider index
> and register offsets are zero. In this case, the current error checking
> against a NULL pointer will fail. Thus, change the API to return a
> ERR_PTR value in an error case, and change all the users of this API to
> check against IS_ERR instead.
>
> Signed-off-by: Tero Kristo <t-kristo@ti.com>
> Acked-by: Michael Turquette <mturquette@linaro.org>

Queued this patch for 4.1 through ti clock driver.

-Tero

> ---
>   drivers/clk/ti/apll.c      |    5 +++--
>   drivers/clk/ti/autoidle.c  |    2 +-
>   drivers/clk/ti/clk.c       |    7 ++++---
>   drivers/clk/ti/divider.c   |    4 ++--
>   drivers/clk/ti/dpll.c      |    6 +++---
>   drivers/clk/ti/gate.c      |    4 ++--
>   drivers/clk/ti/interface.c |    2 +-
>   drivers/clk/ti/mux.c       |    4 ++--
>   8 files changed, 18 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/clk/ti/apll.c b/drivers/clk/ti/apll.c
> index 72d9727..49baf38 100644
> --- a/drivers/clk/ti/apll.c
> +++ b/drivers/clk/ti/apll.c
> @@ -203,7 +203,7 @@ static void __init of_dra7_apll_setup(struct device_node *node)
>   	ad->control_reg = ti_clk_get_reg_addr(node, 0);
>   	ad->idlest_reg = ti_clk_get_reg_addr(node, 1);
>
> -	if (!ad->control_reg || !ad->idlest_reg)
> +	if (IS_ERR(ad->control_reg) || IS_ERR(ad->idlest_reg))
>   		goto cleanup;
>
>   	ad->idlest_mask = 0x1;
> @@ -384,7 +384,8 @@ static void __init of_omap2_apll_setup(struct device_node *node)
>   	ad->autoidle_reg = ti_clk_get_reg_addr(node, 1);
>   	ad->idlest_reg = ti_clk_get_reg_addr(node, 2);
>
> -	if (!ad->control_reg || !ad->autoidle_reg || !ad->idlest_reg)
> +	if (IS_ERR(ad->control_reg) || IS_ERR(ad->autoidle_reg) ||
> +	    IS_ERR(ad->idlest_reg))
>   		goto cleanup;
>
>   	clk = clk_register(NULL, &clk_hw->hw);
> diff --git a/drivers/clk/ti/autoidle.c b/drivers/clk/ti/autoidle.c
> index 8912ff8..e75c64c 100644
> --- a/drivers/clk/ti/autoidle.c
> +++ b/drivers/clk/ti/autoidle.c
> @@ -119,7 +119,7 @@ int __init of_ti_clk_autoidle_setup(struct device_node *node)
>   	clk->name = node->name;
>   	clk->reg = ti_clk_get_reg_addr(node, 0);
>
> -	if (!clk->reg) {
> +	if (IS_ERR(clk->reg)) {
>   		kfree(clk);
>   		return -EINVAL;
>   	}
> diff --git a/drivers/clk/ti/clk.c b/drivers/clk/ti/clk.c
> index e22b956..0ebe5c5 100644
> --- a/drivers/clk/ti/clk.c
> +++ b/drivers/clk/ti/clk.c
> @@ -103,7 +103,8 @@ int __init ti_clk_retry_init(struct device_node *node, struct clk_hw *hw,
>    * @index: register index from the clock node
>    *
>    * Builds clock register address from device tree information. This
> - * is a struct of type clk_omap_reg.
> + * is a struct of type clk_omap_reg. Returns a pointer to the register
> + * address, or a pointer error value in failure.
>    */
>   void __iomem *ti_clk_get_reg_addr(struct device_node *node, int index)
>   {
> @@ -121,14 +122,14 @@ void __iomem *ti_clk_get_reg_addr(struct device_node *node, int index)
>
>   	if (i == CLK_MAX_MEMMAPS) {
>   		pr_err("clk-provider not found for %s!\n", node->name);
> -		return NULL;
> +		return ERR_PTR(-ENOENT);
>   	}
>
>   	reg->index = i;
>
>   	if (of_property_read_u32_index(node, "reg", index, &val)) {
>   		pr_err("%s must have reg[%d]!\n", node->name, index);
> -		return NULL;
> +		return ERR_PTR(-EINVAL);
>   	}
>
>   	reg->offset = val;
> diff --git a/drivers/clk/ti/divider.c b/drivers/clk/ti/divider.c
> index 6211893..ff5f117 100644
> --- a/drivers/clk/ti/divider.c
> +++ b/drivers/clk/ti/divider.c
> @@ -530,8 +530,8 @@ static int __init ti_clk_divider_populate(struct device_node *node,
>   	u32 val;
>
>   	*reg = ti_clk_get_reg_addr(node, 0);
> -	if (!*reg)
> -		return -EINVAL;
> +	if (IS_ERR(*reg))
> +		return PTR_ERR(*reg);
>
>   	if (!of_property_read_u32(node, "ti,bit-shift", &val))
>   		*shift = val;
> diff --git a/drivers/clk/ti/dpll.c b/drivers/clk/ti/dpll.c
> index 81dc469..11478a5 100644
> --- a/drivers/clk/ti/dpll.c
> +++ b/drivers/clk/ti/dpll.c
> @@ -390,18 +390,18 @@ static void __init of_ti_dpll_setup(struct device_node *node,
>   #endif
>   	} else {
>   		dd->idlest_reg = ti_clk_get_reg_addr(node, 1);
> -		if (!dd->idlest_reg)
> +		if (IS_ERR(dd->idlest_reg))
>   			goto cleanup;
>
>   		dd->mult_div1_reg = ti_clk_get_reg_addr(node, 2);
>   	}
>
> -	if (!dd->control_reg || !dd->mult_div1_reg)
> +	if (IS_ERR(dd->control_reg) || IS_ERR(dd->mult_div1_reg))
>   		goto cleanup;
>
>   	if (dd->autoidle_mask) {
>   		dd->autoidle_reg = ti_clk_get_reg_addr(node, 3);
> -		if (!dd->autoidle_reg)
> +		if (IS_ERR(dd->autoidle_reg))
>   			goto cleanup;
>   	}
>
> diff --git a/drivers/clk/ti/gate.c b/drivers/clk/ti/gate.c
> index d493307..0c6fdfc 100644
> --- a/drivers/clk/ti/gate.c
> +++ b/drivers/clk/ti/gate.c
> @@ -225,7 +225,7 @@ static void __init _of_ti_gate_clk_setup(struct device_node *node,
>
>   	if (ops != &omap_gate_clkdm_clk_ops) {
>   		reg = ti_clk_get_reg_addr(node, 0);
> -		if (!reg)
> +		if (IS_ERR(reg))
>   			return;
>
>   		if (!of_property_read_u32(node, "ti,bit-shift", &val))
> @@ -264,7 +264,7 @@ _of_ti_composite_gate_clk_setup(struct device_node *node,
>   		return;
>
>   	gate->enable_reg = ti_clk_get_reg_addr(node, 0);
> -	if (!gate->enable_reg)
> +	if (IS_ERR(gate->enable_reg))
>   		goto cleanup;
>
>   	of_property_read_u32(node, "ti,bit-shift", &val);
> diff --git a/drivers/clk/ti/interface.c b/drivers/clk/ti/interface.c
> index 265d91f..c76230d 100644
> --- a/drivers/clk/ti/interface.c
> +++ b/drivers/clk/ti/interface.c
> @@ -111,7 +111,7 @@ static void __init _of_ti_interface_clk_setup(struct device_node *node,
>   	u32 val;
>
>   	reg = ti_clk_get_reg_addr(node, 0);
> -	if (!reg)
> +	if (IS_ERR(reg))
>   		return;
>
>   	if (!of_property_read_u32(node, "ti,bit-shift", &val))
> diff --git a/drivers/clk/ti/mux.c b/drivers/clk/ti/mux.c
> index 728e253..5cdeed5 100644
> --- a/drivers/clk/ti/mux.c
> +++ b/drivers/clk/ti/mux.c
> @@ -210,7 +210,7 @@ static void of_mux_clk_setup(struct device_node *node)
>
>   	reg = ti_clk_get_reg_addr(node, 0);
>
> -	if (!reg)
> +	if (IS_ERR(reg))
>   		goto cleanup;
>
>   	of_property_read_u32(node, "ti,bit-shift", &shift);
> @@ -283,7 +283,7 @@ static void __init of_ti_composite_mux_clk_setup(struct device_node *node)
>
>   	mux->reg = ti_clk_get_reg_addr(node, 0);
>
> -	if (!mux->reg)
> +	if (IS_ERR(mux->reg))
>   		goto cleanup;
>
>   	if (!of_property_read_u32(node, "ti,bit-shift", &val))
>