Re: [PATCH v15 04/10] USB/ppc4xx: Add Synopsys DWC OTG HCD function

Some more hit-and-run comments.

On Fri, Oct 14, 2011 at 03:08:53PM -0700, tmarri@apm.com wrote:

+static int dwc_otg_hcd_disconnect_cb(void *_p)
+{
+	u32 intr;
+	struct dwc_hcd *hcd = hcd_to_dwc_otg_hcd(_p);
+	struct core_if *core_if = hcd->core_if;
+
+	/* Set status flags for the hub driver. */
+	hcd->flags.b.port_connect_status_change = 1;
+	hcd->flags.b.port_connect_status = 0;
+
+	/*
+	 * Shutdown any transfers in process by clearing the Tx FIFO Empty
+	 * interrupt mask and status bits and disabling subsequent host
+	 * channel interrupts.
+	 */
+	intr = 0;
+	intr |= DWC_INTMSK_NP_TXFIFO_EMPT;
+	intr |= DWC_INTMSK_P_TXFIFO_EMPTY;
+	intr |= DWC_INTMSK_HST_CHAN;
+	spin_lock(&hcd->lock);
+	dwc_reg_modify(gintmsk_reg(hcd), 0, intr, 0);
+	dwc_reg_modify(gintsts_reg(hcd), 0, intr, 0);
+	spin_unlock(&hcd->lock);
+
+	del_timers(hcd);
+
+	/*
+	 * Turn off the vbus power only if the core has transitioned to device
+	 * mode. If still in host mode, need to keep power on to detect a
+	 * reconnection.
+	 */
+	if (dwc_otg_is_device_mode(core_if)) {
+		if (core_if->xceiv->state != OTG_STATE_A_SUSPEND) {
+			u32 hprt0 = 0;
+
+			pr_info("Disconnect: PortPower off\n");
+			hprt0 = DWC_HPRT0_PRT_PWR_RW(hprt0, 0);
+			dwc_reg_write(core_if->host_if->hprt0, 0, hprt0);
+		}
+		dwc_otg_disable_host_interrupts(core_if);
+	}
+
+	/* Respond with an error status to all URBs in the schedule. */
+	kill_all_urbs(hcd);
+	if (dwc_otg_is_host_mode(core_if)) {
+		/* Clean up any host channels that were in use. */
+		int num_channels;
+		u32 i;
+		struct dwc_hc *channel;
+		ulong regs;
+		u32 hcchar;

If you need these many local variables here, and this much indentation, then
please refactor to a helper function. That will get rid of the crazy
linewrapping below too.

+
+		num_channels = core_if->core_params->host_channels;
+		if (!core_if->dma_enable) {
+			/* Flush out any channel requests in slave mode. */
+			for (i = 0; i < num_channels; i++) {
+				channel = hcd->hc_ptr_array[i];
+				if (list_empty(&channel->hc_list_entry)) {
+					regs =
+					    core_if->host_if->hc_regs[i];
+					hcchar = dwc_reg_read(regs, DWC_HCCHAR);
+
+					if (DWC_HCCHAR_ENA_RD(hcchar)) {
+						hcchar =
+						    DWC_HCCHAR_ENA_RW(hcchar,
+								      0);
+						hcchar =
+						    DWC_HCCHAR_DIS_RW(hcchar,
+								      1);
+						hcchar =
+						    DWC_HCCHAR_EPDIR_RW(hcchar,
+									0);
+						dwc_reg_write(regs, DWC_HCCHAR,
+							    hcchar);
+					}
+				}
+			}
+		}
+
+		for (i = 0; i < num_channels; i++) {
+			channel = hcd->hc_ptr_array[i];
+			if (list_empty(&channel->hc_list_entry)) {
+				regs = core_if->host_if->hc_regs[i];
+				hcchar = dwc_reg_read(regs, DWC_HCCHAR);
+
+				if (DWC_HCCHAR_ENA_RD(hcchar)) {
+					/* Halt the channel. */
+					hcchar = DWC_HCCHAR_DIS_RW(hcchar, 1);
+					dwc_reg_write(regs, DWC_HCCHAR, hcchar);
+				}
+				dwc_otg_hc_cleanup(core_if, channel);
+				list_add_tail(&channel->hc_list_entry,
+					      &hcd->free_hc_list);
+			}
+		}
+	}
+
+	/*
+	 * A disconnect will end the session so the B-Device is no
+	 * longer a B-host.
+	 */
+	((struct usb_hcd *)_p)->self.is_b_host = 0;
+	return 1;
+}
+

-Olof