129 lines
3.5 KiB
C
Executable file
129 lines
3.5 KiB
C
Executable file
/*
|
|
* omap-ocp2scp.c - transform ocp interface protocol to scp protocol
|
|
*
|
|
* Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* Author: Kishon Vijay Abraham I <kishon@ti.com>
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
*/
|
|
|
|
#include <linux/io.h>
|
|
#include <linux/module.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/err.h>
|
|
#include <linux/pm_runtime.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_platform.h>
|
|
|
|
#define OCP2SCP_TIMING 0x18
|
|
#define SYNC2_MASK 0xf
|
|
|
|
static int ocp2scp_remove_devices(struct device *dev, void *c)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(dev);
|
|
|
|
platform_device_unregister(pdev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int omap_ocp2scp_probe(struct platform_device *pdev)
|
|
{
|
|
int ret;
|
|
u32 reg;
|
|
void __iomem *regs;
|
|
struct resource *res;
|
|
struct device_node *np = pdev->dev.of_node;
|
|
|
|
if (np) {
|
|
ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
|
|
if (ret) {
|
|
dev_err(&pdev->dev,
|
|
"failed to add resources for ocp2scp child\n");
|
|
goto err0;
|
|
}
|
|
}
|
|
|
|
pm_runtime_enable(&pdev->dev);
|
|
/*
|
|
* As per AM572x TRM: http://www.ti.com/lit/ug/spruhz6/spruhz6.pdf
|
|
* under section 26.3.2.2, table 26-26 OCP2SCP TIMING Caution;
|
|
* As per OMAP4430 TRM: http://www.ti.com/lit/ug/swpu231ap/swpu231ap.pdf
|
|
* under section 23.12.6.2.2 , Table 23-1213 OCP2SCP TIMING Caution;
|
|
* As per OMAP4460 TRM: http://www.ti.com/lit/ug/swpu235ab/swpu235ab.pdf
|
|
* under section 23.12.6.2.2, Table 23-1213 OCP2SCP TIMING Caution;
|
|
* As per OMAP543x TRM http://www.ti.com/lit/pdf/swpu249
|
|
* under section 27.3.2.2, Table 27-27 OCP2SCP TIMING Caution;
|
|
*
|
|
* Read path of OCP2SCP is not working properly due to low reset value
|
|
* of SYNC2 parameter in OCP2SCP. Suggested reset value is 0x6 or more.
|
|
*/
|
|
if (!of_device_is_compatible(np, "ti,am437x-ocp2scp")) {
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
regs = devm_ioremap_resource(&pdev->dev, res);
|
|
if (IS_ERR(regs)) {
|
|
ret = PTR_ERR(regs);
|
|
goto err1;
|
|
}
|
|
|
|
pm_runtime_get_sync(&pdev->dev);
|
|
reg = readl_relaxed(regs + OCP2SCP_TIMING);
|
|
reg &= ~(SYNC2_MASK);
|
|
reg |= 0x6;
|
|
writel_relaxed(reg, regs + OCP2SCP_TIMING);
|
|
pm_runtime_put_sync(&pdev->dev);
|
|
}
|
|
|
|
return 0;
|
|
|
|
err1:
|
|
pm_runtime_disable(&pdev->dev);
|
|
|
|
err0:
|
|
device_for_each_child(&pdev->dev, NULL, ocp2scp_remove_devices);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int omap_ocp2scp_remove(struct platform_device *pdev)
|
|
{
|
|
pm_runtime_disable(&pdev->dev);
|
|
device_for_each_child(&pdev->dev, NULL, ocp2scp_remove_devices);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_OF
|
|
static const struct of_device_id omap_ocp2scp_id_table[] = {
|
|
{ .compatible = "ti,omap-ocp2scp" },
|
|
{ .compatible = "ti,am437x-ocp2scp" },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, omap_ocp2scp_id_table);
|
|
#endif
|
|
|
|
static struct platform_driver omap_ocp2scp_driver = {
|
|
.probe = omap_ocp2scp_probe,
|
|
.remove = omap_ocp2scp_remove,
|
|
.driver = {
|
|
.name = "omap-ocp2scp",
|
|
.of_match_table = of_match_ptr(omap_ocp2scp_id_table),
|
|
},
|
|
};
|
|
|
|
module_platform_driver(omap_ocp2scp_driver);
|
|
|
|
MODULE_ALIAS("platform:omap-ocp2scp");
|
|
MODULE_AUTHOR("Texas Instruments Inc.");
|
|
MODULE_DESCRIPTION("OMAP OCP2SCP driver");
|
|
MODULE_LICENSE("GPL v2");
|