linux/drivers/usb/host/ehci-atmel.c
Linus Torvalds 8ceafbfa91 Merge branch 'for-linus-dma-masks' of git://git.linaro.org/people/rmk/linux-arm
Pull DMA mask updates from Russell King:
 "This series cleans up the handling of DMA masks in a lot of drivers,
  fixing some bugs as we go.

  Some of the more serious errors include:
   - drivers which only set their coherent DMA mask if the attempt to
     set the streaming mask fails.
   - drivers which test for a NULL dma mask pointer, and then set the
     dma mask pointer to a location in their module .data section -
     which will cause problems if the module is reloaded.

  To counter these, I have introduced two helper functions:
   - dma_set_mask_and_coherent() takes care of setting both the
     streaming and coherent masks at the same time, with the correct
     error handling as specified by the API.
   - dma_coerce_mask_and_coherent() which resolves the problem of
     drivers forcefully setting DMA masks.  This is more a marker for
     future work to further clean these locations up - the code which
     creates the devices really should be initialising these, but to fix
     that in one go along with this change could potentially be very
     disruptive.

  The last thing this series does is prise away some of Linux's addition
  to "DMA addresses are physical addresses and RAM always starts at
  zero".  We have ARM LPAE systems where all system memory is above 4GB
  physical, hence having DMA masks interpreted by (eg) the block layers
  as describing physical addresses in the range 0..DMAMASK fails on
  these platforms.  Santosh Shilimkar addresses this in this series; the
  patches were copied to the appropriate people multiple times but were
  ignored.

  Fixing this also gets rid of some ARM weirdness in the setup of the
  max*pfn variables, and brings ARM into line with every other Linux
  architecture as far as those go"

* 'for-linus-dma-masks' of git://git.linaro.org/people/rmk/linux-arm: (52 commits)
  ARM: 7805/1: mm: change max*pfn to include the physical offset of memory
  ARM: 7797/1: mmc: Use dma_max_pfn(dev) helper for bounce_limit calculations
  ARM: 7796/1: scsi: Use dma_max_pfn(dev) helper for bounce_limit calculations
  ARM: 7795/1: mm: dma-mapping: Add dma_max_pfn(dev) helper function
  ARM: 7794/1: block: Rename parameter dma_mask to max_addr for blk_queue_bounce_limit()
  ARM: DMA-API: better handing of DMA masks for coherent allocations
  ARM: 7857/1: dma: imx-sdma: setup dma mask
  DMA-API: firmware/google/gsmi.c: avoid direct access to DMA masks
  DMA-API: dcdbas: update DMA mask handing
  DMA-API: dma: edma.c: no need to explicitly initialize DMA masks
  DMA-API: usb: musb: use platform_device_register_full() to avoid directly messing with dma masks
  DMA-API: crypto: remove last references to 'static struct device *dev'
  DMA-API: crypto: fix ixp4xx crypto platform device support
  DMA-API: others: use dma_set_coherent_mask()
  DMA-API: staging: use dma_set_coherent_mask()
  DMA-API: usb: use new dma_coerce_mask_and_coherent()
  DMA-API: usb: use dma_set_coherent_mask()
  DMA-API: parport: parport_pc.c: use dma_coerce_mask_and_coherent()
  DMA-API: net: octeon: use dma_coerce_mask_and_coherent()
  DMA-API: net: nxp/lpc_eth: use dma_coerce_mask_and_coherent()
  ...
2013-11-14 07:55:21 +09:00

223 lines
5.1 KiB
C

/*
* Driver for EHCI UHP on Atmel chips
*
* Copyright (C) 2009 Atmel Corporation,
* Nicolas Ferre <nicolas.ferre@atmel.com>
*
* Based on various ehci-*.c drivers
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive for
* more details.
*/
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include "ehci.h"
#define DRIVER_DESC "EHCI Atmel driver"
static const char hcd_name[] = "ehci-atmel";
static struct hc_driver __read_mostly ehci_atmel_hc_driver;
/* interface and function clocks */
static struct clk *iclk, *fclk, *uclk;
static int clocked;
/*-------------------------------------------------------------------------*/
static void atmel_start_clock(void)
{
if (IS_ENABLED(CONFIG_COMMON_CLK)) {
clk_set_rate(uclk, 48000000);
clk_prepare_enable(uclk);
}
clk_prepare_enable(iclk);
clk_prepare_enable(fclk);
clocked = 1;
}
static void atmel_stop_clock(void)
{
clk_disable_unprepare(fclk);
clk_disable_unprepare(iclk);
if (IS_ENABLED(CONFIG_COMMON_CLK))
clk_disable_unprepare(uclk);
clocked = 0;
}
static void atmel_start_ehci(struct platform_device *pdev)
{
dev_dbg(&pdev->dev, "start\n");
atmel_start_clock();
}
static void atmel_stop_ehci(struct platform_device *pdev)
{
dev_dbg(&pdev->dev, "stop\n");
atmel_stop_clock();
}
/*-------------------------------------------------------------------------*/
static int ehci_atmel_drv_probe(struct platform_device *pdev)
{
struct usb_hcd *hcd;
const struct hc_driver *driver = &ehci_atmel_hc_driver;
struct resource *res;
struct ehci_hcd *ehci;
int irq;
int retval;
if (usb_disabled())
return -ENODEV;
pr_debug("Initializing Atmel-SoC USB Host Controller\n");
irq = platform_get_irq(pdev, 0);
if (irq <= 0) {
dev_err(&pdev->dev,
"Found HC with no IRQ. Check %s setup!\n",
dev_name(&pdev->dev));
retval = -ENODEV;
goto fail_create_hcd;
}
/* Right now device-tree probed devices don't get dma_mask set.
* Since shared usb code relies on it, set it here for now.
* Once we have dma capability bindings this can go away.
*/
retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
if (retval)
goto fail_create_hcd;
hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
if (!hcd) {
retval = -ENOMEM;
goto fail_create_hcd;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(&pdev->dev,
"Found HC with no register addr. Check %s setup!\n",
dev_name(&pdev->dev));
retval = -ENODEV;
goto fail_request_resource;
}
hcd->rsrc_start = res->start;
hcd->rsrc_len = resource_size(res);
hcd->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(hcd->regs)) {
retval = PTR_ERR(hcd->regs);
goto fail_request_resource;
}
iclk = devm_clk_get(&pdev->dev, "ehci_clk");
if (IS_ERR(iclk)) {
dev_err(&pdev->dev, "Error getting interface clock\n");
retval = -ENOENT;
goto fail_request_resource;
}
fclk = devm_clk_get(&pdev->dev, "uhpck");
if (IS_ERR(fclk)) {
dev_err(&pdev->dev, "Error getting function clock\n");
retval = -ENOENT;
goto fail_request_resource;
}
if (IS_ENABLED(CONFIG_COMMON_CLK)) {
uclk = devm_clk_get(&pdev->dev, "usb_clk");
if (IS_ERR(uclk)) {
dev_err(&pdev->dev, "failed to get uclk\n");
retval = PTR_ERR(uclk);
goto fail_request_resource;
}
}
ehci = hcd_to_ehci(hcd);
/* registers start at offset 0x0 */
ehci->caps = hcd->regs;
atmel_start_ehci(pdev);
retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
if (retval)
goto fail_add_hcd;
return retval;
fail_add_hcd:
atmel_stop_ehci(pdev);
fail_request_resource:
usb_put_hcd(hcd);
fail_create_hcd:
dev_err(&pdev->dev, "init %s fail, %d\n",
dev_name(&pdev->dev), retval);
return retval;
}
static int ehci_atmel_drv_remove(struct platform_device *pdev)
{
struct usb_hcd *hcd = platform_get_drvdata(pdev);
usb_remove_hcd(hcd);
usb_put_hcd(hcd);
atmel_stop_ehci(pdev);
fclk = iclk = NULL;
return 0;
}
#ifdef CONFIG_OF
static const struct of_device_id atmel_ehci_dt_ids[] = {
{ .compatible = "atmel,at91sam9g45-ehci" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
#endif
static struct platform_driver ehci_atmel_driver = {
.probe = ehci_atmel_drv_probe,
.remove = ehci_atmel_drv_remove,
.shutdown = usb_hcd_platform_shutdown,
.driver = {
.name = "atmel-ehci",
.of_match_table = of_match_ptr(atmel_ehci_dt_ids),
},
};
static int __init ehci_atmel_init(void)
{
if (usb_disabled())
return -ENODEV;
pr_info("%s: " DRIVER_DESC "\n", hcd_name);
ehci_init_driver(&ehci_atmel_hc_driver, NULL);
return platform_driver_register(&ehci_atmel_driver);
}
module_init(ehci_atmel_init);
static void __exit ehci_atmel_cleanup(void)
{
platform_driver_unregister(&ehci_atmel_driver);
}
module_exit(ehci_atmel_cleanup);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_ALIAS("platform:atmel-ehci");
MODULE_AUTHOR("Nicolas Ferre");
MODULE_LICENSE("GPL");