drivers: net: cpsw: fix for cpsw crash when build as modules

When CPSW and Davinci MDIO are build as modules, CPSW crashes when accessing CPSW registers in CPSW probe. The same is working in built-in as the CPSW clocks are enabled in Davindi MDIO probe, SO Enabling the clocks before accessing the version register and moving out the other register access to cpsw device open. Signed-off-by: Mugunthan V N <[email protected]> Signed-off-by: Felipe Balbi <[email protected]> Signed-off-by: David S. Miller <[email protected]>
AshishNamdev · AshishNamdev · Dec 22, 2013 · Dec 11, 2013 · Jan 10, 2013 · Dec 12, 2013
commit f280e89ad6a29d9969cb6b216123c798e1689bc4
diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
@@ -1151,6 +1151,12 @@ static int cpsw_ndo_open(struct net_device *ndev)
 		 * receive descs
 		 */
 		cpsw_info(priv, ifup, "submitted %d rx descriptors\n", i);
+
+		if (cpts_register(&priv->pdev->dev, priv->cpts,
+				  priv->data.cpts_clock_mult,
+				  priv->data.cpts_clock_shift))
+			dev_err(priv->dev, "error registering cpts device\n");
+
 	}
 
 	/* Enable Interrupt pacing if configured */
@@ -1197,6 +1203,7 @@ static int cpsw_ndo_stop(struct net_device *ndev)
 	netif_carrier_off(priv->ndev);
 
 	if (cpsw_common_res_usage_state(priv) <= 1) {
+		cpts_unregister(priv->cpts);
 		cpsw_intr_disable(priv);
 		cpdma_ctlr_int_ctrl(priv->dma, false);
 		cpdma_ctlr_stop(priv->dma);
@@ -1985,9 +1992,15 @@ static int cpsw_probe(struct platform_device *pdev)
 		goto clean_runtime_disable_ret;
 	}
 	priv->regs = ss_regs;
-	priv->version = __raw_readl(&priv->regs->id_ver);
 	priv->host_port = HOST_PORT_NUM;
 
+	/* Need to enable clocks with runtime PM api to access module
+	 * registers
+	 */
+	pm_runtime_get_sync(&pdev->dev);
+	priv->version = readl(&priv->regs->id_ver);
+	pm_runtime_put_sync(&pdev->dev);
+
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 	priv->wr_regs = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(priv->wr_regs)) {
@@ -2157,8 +2170,6 @@ static int cpsw_remove(struct platform_device *pdev)
 		unregister_netdev(cpsw_get_slave_ndev(priv, 1));
 	unregister_netdev(ndev);
 
-	cpts_unregister(priv->cpts);
-
 	cpsw_ale_destroy(priv->ale);
 	cpdma_chan_destroy(priv->txch);
 	cpdma_chan_destroy(priv->rxch);