omap: McBSP: Fix possible port lockout

In its current form, the omap_mcbsp_request() function can return after
irq_request() failure without any cleanups, effectively locking out the port
forever with clocks left running. Fix it.

Signed-off-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Acked-by: Jarkko Nikula <jhnikula@gmail.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

diff --git a/arch/arm/plat-omap/mcbsp.c b/arch/arm/plat-omap/mcbsp.c
index 2cc1cc3..f757672 100644 (file)
--- a/arch/arm/plat-omap/mcbsp.c
+++ b/arch/arm/plat-omap/mcbsp.c
@@ -436,7 +436,7 @@ int omap_mcbsp_request(unsigned int id)
                        dev_err(mcbsp->dev, "Unable to request TX IRQ %d "
                                        "for McBSP%d\n", mcbsp->tx_irq,
                                        mcbsp->id);
-                       return err;
+                       goto error;
                }
 
                init_completion(&mcbsp->rx_irq_completion);
@@ -446,12 +446,26 @@ int omap_mcbsp_request(unsigned int id)
                        dev_err(mcbsp->dev, "Unable to request RX IRQ %d "
                                        "for McBSP%d\n", mcbsp->rx_irq,
                                        mcbsp->id);
-                       free_irq(mcbsp->tx_irq, (void *)mcbsp);
-                       return err;
+                       goto tx_irq;
                }
        }
 
        return 0;
+tx_irq:
+       free_irq(mcbsp->tx_irq, (void *)mcbsp);
+error:
+       if (mcbsp->pdata && mcbsp->pdata->ops && mcbsp->pdata->ops->free)
+                       mcbsp->pdata->ops->free(id);
+
+       /* Do procedure specific to omap34xx arch, if applicable */
+       omap34xx_mcbsp_free(mcbsp);
+
+       clk_disable(mcbsp->fclk);
+       clk_disable(mcbsp->iclk);
+
+       mcbsp->free = 1;
+
+       return err;
 }
 EXPORT_SYMBOL(omap_mcbsp_request);