On Tue, 2018-10-16 at 13:03 -0300, Fabio Estevam wrote:

quoted

+       /* DCP clock is optional, only used on some SOCs */
+       sdcp->dcp_clk = devm_clk_get(dev, "dcp");
+       if (IS_ERR(sdcp->dcp_clk)) {
+               if (sdcp->dcp_clk != ERR_PTR(-ENOENT))
+                       return PTR_ERR(sdcp->dcp_clk);
+               sdcp->dcp_clk = NULL;

This dcp_clk assignment to NULL does not seem to be necessary.

The clk API ignores all calls if clk == NULL (which is very nice) but
not if IS_ERR(clk). Setting dcp_clk to NULL avoids sprinkling other
checks.

quoted

+       ret = clk_prepare_enable(sdcp->dcp_clk);
+       if (ret)
+               return ret;

        ret = devm_request_irq(dev, dcp_vmi_irq, mxs_dcp_irq, 0,
                               "dcp-vmi-irq", sdcp);
        if (ret) {
                dev_err(dev, "Failed to claim DCP VMI IRQ!\n");

In case of subsequent errors you should call
clk_disable_unprepare(sdcp->dcp_clk).

Yes, will resend. Maybe some day clk consumer will automatically undo
pending prepare/enables on release?