/*
* EIM driver for Freescale's i.MX chips
*
* Copyright (C) 2013 Freescale Semiconductor, Inc.
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/module.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/of_address.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/mfd/syscon.h>
#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
#include <linux/regmap.h>
struct imx_weim_devtype {
unsigned int cs_count;
unsigned int cs_regs_count;
unsigned int cs_stride;
unsigned int wcr_offset;
unsigned int wcr_bcm;
unsigned int wcr_cont_bclk;
};
static const struct imx_weim_devtype imx1_weim_devtype = {
.cs_count = 6,
.cs_regs_count = 2,
.cs_stride = 0x08,
};
static const struct imx_weim_devtype imx27_weim_devtype = {
.cs_count = 6,
.cs_regs_count = 3,
.cs_stride = 0x10,
};
static const struct imx_weim_devtype imx50_weim_devtype = {
.cs_count = 4,
.cs_regs_count = 6,
.cs_stride = 0x18,
.wcr_offset = 0x90,
.wcr_bcm = BIT(0),
.wcr_cont_bclk = BIT(3),
};
static const struct imx_weim_devtype imx51_weim_devtype = {
.cs_count = 6,
.cs_regs_count = 6,
.cs_stride = 0x18,
};
#define MAX_CS_REGS_COUNT 6
#define MAX_CS_COUNT 6
#define OF_REG_SIZE 3
struct cs_timing {
bool is_applied;
u32 regs[MAX_CS_REGS_COUNT];
};
struct cs_timing_state {
struct cs_timing cs[MAX_CS_COUNT];
};
struct weim_priv {
void __iomem *base;
struct cs_timing_state timing_state;
};
static const struct of_device_id weim_id_table[] = {
/* i.MX1/21 */
{ .compatible = "fsl,imx1-weim", .data = &imx1_weim_devtype, },
/* i.MX25/27/31/35 */
{ .compatible = "fsl,imx27-weim", .data = &imx27_weim_devtype, },
/* i.MX50/53/6Q */
{ .compatible = "fsl,imx50-weim", .data = &imx50_weim_devtype, },
{ .compatible = "fsl,imx6q-weim", .data = &imx50_weim_devtype, },
/* i.MX51 */
{ .compatible = "fsl,imx51-weim", .data = &imx51_weim_devtype, },
{ }
};
MODULE_DEVICE_TABLE(of, weim_id_table);
static int imx_weim_gpr_setup(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct of_range_parser parser;
struct of_range range;
struct regmap *gpr;
u32 gprvals[4] = {
05, /* CS0(128M) CS1(0M) CS2(0M) CS3(0M) */
033, /* CS0(64M) CS1(64M) CS2(0M) CS3(0M) */
0113, /* CS0(64M) CS1(32M) CS2(32M) CS3(0M) */
01111, /* CS0(32M) CS1(32M) CS2(32M) CS3(32M) */
};
u32 gprval = 0;
u32 val;
int cs = 0;
int i = 0;
gpr = syscon_regmap_lookup_by_phandle(np, "fsl,weim-cs-gpr");
if (IS_ERR(gpr)) {
dev_dbg(&pdev->dev, "failed to find weim-cs-gpr\n");
return 0;
}
if (of_range_parser_init(&parser, np))
goto err;
for_each_of_range(&parser, &range) {
cs = range.bus_addr >> 32;
val = (range.size / SZ_32M) | 1;
gprval |= val << cs * 3;
i++;
}
if (i == 0)
goto err;
for (i = 0; i < ARRAY_SIZE(gprvals); i++) {
if (gprval == gprvals[i]) {
/* Found it. Set up IOMUXC_GPR1[11:0] with it. */
regmap_update_bits(gpr, IOMUXC_GPR1, 0xfff, gprval);
return 0;
}
}
err:
dev_err(&pdev->dev, "Invalid 'ranges' configuration\n");
return -EINVAL;
}
/* Parse and set the timing for this device. */
static int weim_timing_setup(struct device *dev, struct device_node *np,
const struct imx_weim_devtype *devtype)
{
u32 cs_idx, value[MAX_CS_REGS_COUNT];
int i, ret;
int reg_idx, num_regs;
struct cs_timing *cst;
struct weim_priv *priv;
struct cs_timing_state *ts;
void __iomem *base;
if (WARN_ON(devtype->cs_regs_count > MAX_CS_REGS_COUNT))
return -EINVAL;
if (WARN_ON(devtype->cs_count > MAX_CS_COUNT))
return -EINVAL;
priv = dev_get_drvdata(dev);
base = priv->base;
ts = &priv->timing_state;
ret = of_property_read_u32_array(np, "fsl,weim-cs-timing",
value, devtype->cs_regs_count);
if (ret)
return ret;
/*
* the child node's "reg" property may contain multiple address ranges,
* extract the chip select for each.
*/
num_regs = of_property_count_elems_of_size(np, "reg", OF_REG_SIZE);
if (num_regs < 0)
return num_regs;
if (!num_regs)
return -EINVAL;
for (reg_idx = 0; reg_idx < num_regs; reg_idx++) {
/* get the CS index from this child node's "reg" property. */
ret = of_property_read_u32_index(np, "reg",
reg_idx * OF_REG_SIZE, &cs_idx);
if (ret)
break;
if (cs_idx >= devtype->cs_count)
return -EINVAL;
/* prevent re-configuring a CS that's already been configured */
cst = &ts->cs[cs_idx];
if (cst->is_applied && memcmp(value, cst->regs,
devtype->cs_regs_count * sizeof(u32))) {
dev_err(dev, "fsl,weim-cs-timing conflict on %pOF", np);
return -EINVAL;
}
/* set the timing for WEIM */
for (i = 0; i < devtype->cs_regs_count; i++)
writel(value[i],
base + cs_idx * devtype->cs_stride + i * 4);
if (!cst->is_applied) {
cst->is_applied = true;
memcpy(cst->regs, value,
devtype->cs_regs_count * sizeof(u32));
}
}
return 0;
}
static int weim_parse_dt(struct platform_device *pdev)
{
const struct imx_weim_devtype *devtype = device_get_match_data(&pdev->dev);
int ret = 0, have_child = 0;
struct device_node *child;
struct weim_priv *priv;
void __iomem *base;
u32 reg;
if (devtype == &imx50_weim_devtype) {
ret = imx_weim_gpr_setup(pdev);
if (ret)
return ret;
}
priv = dev_get_drvdata(&pdev->dev);
base = priv->base;
if (of_property_read_bool(pdev->dev.of_node, "fsl,burst-clk-enable")) {
if (devtype->wcr_bcm) {
reg = readl(base + devtype->wcr_offset);
reg |= devtype->wcr_bcm;
if (of_property_read_bool(pdev->dev.of_node,
"fsl,continuous-burst-clk")) {
if (devtype->wcr_cont_bclk) {
reg |= devtype->wcr_cont_bclk;
} else {
dev_err(&pdev->dev,
"continuous burst clk not supported.\n");
return -EINVAL;
}
}
writel(reg, base + devtype->wcr_offset);
} else {
dev_err(&pdev->dev, "burst clk mode not supported.\n");
return -EINVAL;
}
}
for_each_available_child_of_node(pdev->dev.of_node, child) {
ret = weim_timing_setup(&pdev->dev, child, devtype);
if (ret)
dev_warn(&pdev->dev, "%pOF set timing failed.\n",
child);
else
have_child = 1;
}
if (have_child)
ret = of_platform_default_populate(pdev->dev.of_node,
NULL, &pdev->dev);
if (ret)
dev_err(&pdev->dev, "%pOF fail to create devices.\n",
pdev->dev.of_node);
return ret;
}
static int weim_probe(struct platform_device *pdev)
{
struct weim_priv *priv;
struct clk *clk;
void __iomem *base;
int ret;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
/* get the resource */
base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(base))
return PTR_ERR(base);
priv->base = base;
dev_set_drvdata(&pdev->dev, priv);
/* get the clock */
clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(clk))
return PTR_ERR(clk);
ret = clk_prepare_enable(clk);
if (ret)
return ret;
/* parse the device node */
ret = weim_parse_dt(pdev);
if (ret)
clk_disable_unprepare(clk);
else
dev_info(&pdev->dev, "Driver registered.\n");
return ret;
}
#if IS_ENABLED(CONFIG_OF_DYNAMIC)
static int of_weim_notify(struct notifier_block *nb, unsigned long action,
void *arg)
{
const struct imx_weim_devtype *devtype;
struct of_reconfig_data *rd = arg;
const struct of_device_id *of_id;
struct platform_device *pdev;
int ret = NOTIFY_OK;
switch (of_reconfig_get_state_change(action, rd)) {
case OF_RECONFIG_CHANGE_ADD:
of_id = of_match_node(weim_id_table, rd->dn->parent);
if (!of_id)
return NOTIFY_OK; /* not for us */
devtype = of_id->data;
pdev = of_find_device_by_node(rd->dn->parent);
if (!pdev) {
pr_err("%s: could not find platform device for '%pOF'\n",
__func__, rd->dn->parent);
return notifier_from_errno(-EINVAL);
}
if (weim_timing_setup(&pdev->dev, rd->dn, devtype))
dev_warn(&pdev->dev,
"Failed to setup timing for '%pOF'\n", rd->dn);
if (!of_node_check_flag(rd->dn, OF_POPULATED)) {
/*
* Clear the flag before adding the device so that
* fw_devlink doesn't skip adding consumers to this
* device.
*/
rd->dn->fwnode.flags &= ~FWNODE_FLAG_NOT_DEVICE;
if (!of_platform_device_create(rd->dn, NULL, &pdev->dev)) {
dev_err(&pdev->dev,
"Failed to create child device '%pOF'\n",
rd->dn);
ret = notifier_from_errno(-EINVAL);
}
}
platform_device_put(pdev);
break;
case OF_RECONFIG_CHANGE_REMOVE:
if (!of_node_check_flag(rd->dn, OF_POPULATED))
return NOTIFY_OK; /* device already destroyed */
of_id = of_match_node(weim_id_table, rd->dn->parent);
if (!of_id)
return NOTIFY_OK; /* not for us */
pdev = of_find_device_by_node(rd->dn);
if (!pdev) {
pr_err("Could not find platform device for '%pOF'\n",
rd->dn);
ret = notifier_from_errno(-EINVAL);
} else {
of_platform_device_destroy(&pdev->dev, NULL);
platform_device_put(pdev);
}
break;
default:
break;
}
return ret;
}
static struct notifier_block weim_of_notifier = {
.notifier_call = of_weim_notify,
};
#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */
static struct platform_driver weim_driver = {
.driver = {
.name = "imx-weim",
.of_match_table = weim_id_table,
},
.probe = weim_probe,
};
static int __init weim_init(void)
{
#if IS_ENABLED(CONFIG_OF_DYNAMIC)
WARN_ON(of_reconfig_notifier_register(&weim_of_notifier));
#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */
return platform_driver_register(&weim_driver);
}
module_init(weim_init);
static void __exit weim_exit(void)
{
#if IS_ENABLED(CONFIG_OF_DYNAMIC)
of_reconfig_notifier_unregister(&weim_of_notifier);
#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */
return platform_driver_unregister(&weim_driver);
}
module_exit(weim_exit);
MODULE_AUTHOR("Freescale Semiconductor Inc.");
MODULE_DESCRIPTION("i.MX EIM Controller Driver");
MODULE_LICENSE("GPL");
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