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 <mugunthanvnm@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
index a91f0c9d4511e23a9189f84916d4be158157813d..5120d9ce1dd4cdbdd8608550f87392d0a5f6bbb9 100644 (file)
--- 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);