On Tue, May 09, 2023 at 10:27:28AM +0800, Jiawen Wu wrote:
> In order for I2C to be able to work in standard mode, register a fixed
> rate clock for each I2C device.
>
> Signed-off-by: Jiawen Wu <jiawenwu@xxxxxxxxxxxxxx>
...
> @@ -70,6 +72,32 @@ static int txgbe_swnodes_register(struct txgbe *txgbe)
> return software_node_register_node_group(nodes->group);
> }
>
> +static int txgbe_clock_register(struct txgbe *txgbe)
> +{
> + struct pci_dev *pdev = txgbe->wx->pdev;
> + struct clk_lookup *clock;
> + char clk_name[32];
> + struct clk *clk;
> +
> + snprintf(clk_name, sizeof(clk_name), "i2c_designware.%d",
> + (pdev->bus->number << 8) | pdev->devfn);
> +
> + clk = clk_register_fixed_rate(NULL, clk_name, NULL, 0, 156250000);
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
> +
> + clock = clkdev_create(clk, NULL, clk_name);
> + if (!clock) {
> + clk_unregister(clk);
> + return PTR_ERR(clock);
Hi Jiawen,
Sorry for missing this earlier, but the above error handling doesn't seem
right.
* This error condition is met if clock == NULL
* So the above is returning PTR_ERR(NULL), which is a yellow flag to me.
In any case, PTR_ERR(NULL) => 0 is returned on error.
* The caller treats a 0 return value as success.
Perhaps this should be: return -ENOMEM?
> + }
> +
> + txgbe->clk = clk;
> + txgbe->clock = clock;
> +
> + return 0;
> +}
> +
> int txgbe_init_phy(struct txgbe *txgbe)
> {
> int ret;
> @@ -80,10 +108,23 @@ int txgbe_init_phy(struct txgbe *txgbe)
> return ret;
> }
>
> + ret = txgbe_clock_register(txgbe);
> + if (ret) {
> + wx_err(txgbe->wx, "failed to register clock: %d\n", ret);
> + goto err_unregister_swnode;
> + }
> +
> return 0;
...
