mfd: ocelot: Add helper to get regmap from a resource

Several ocelot-related modules are designed for MMIO / regmaps. As such,
they often use a combination of devm_platform_get_and_ioremap_resource()
and devm_regmap_init_mmio().

Operating in an MFD might be different, in that it could be memory mapped,
or it could be SPI, I2C... In these cases a fallback to use IORESOURCE_REG
instead of IORESOURCE_MEM becomes necessary.

When this happens, there's redundant logic that needs to be implemented in
every driver. In order to avoid this redundancy, utilize a single function
that, if the MFD scenario is enabled, will perform this fallback logic.

Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20220905162132.2943088-2-colin.foster@in-advantage.com
This commit is contained in:
Colin Foster 2022-09-05 09:21:25 -07:00 коммит произвёл Lee Jones
Родитель 568035b01c
Коммит bb5721f063
2 изменённых файлов: 67 добавлений и 0 удалений

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@ -14741,6 +14741,11 @@ F: net/dsa/tag_ocelot.c
F: net/dsa/tag_ocelot_8021q.c
F: tools/testing/selftests/drivers/net/ocelot/*
OCELOT EXTERNAL SWITCH CONTROL
M: Colin Foster <colin.foster@in-advantage.com>
S: Supported
F: include/linux/mfd/ocelot.h
OCXL (Open Coherent Accelerator Processor Interface OpenCAPI) DRIVER
M: Frederic Barrat <fbarrat@linux.ibm.com>
M: Andrew Donnellan <ajd@linux.ibm.com>

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@ -0,0 +1,62 @@
/* SPDX-License-Identifier: GPL-2.0 OR MIT */
/* Copyright 2022 Innovative Advantage Inc. */
#ifndef _LINUX_MFD_OCELOT_H
#define _LINUX_MFD_OCELOT_H
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/types.h>
struct resource;
static inline struct regmap *
ocelot_regmap_from_resource_optional(struct platform_device *pdev,
unsigned int index,
const struct regmap_config *config)
{
struct device *dev = &pdev->dev;
struct resource *res;
void __iomem *regs;
/*
* Don't use _get_and_ioremap_resource() here, since that will invoke
* prints of "invalid resource" which will simply add confusion.
*/
res = platform_get_resource(pdev, IORESOURCE_MEM, index);
if (res) {
regs = devm_ioremap_resource(dev, res);
if (IS_ERR(regs))
return ERR_CAST(regs);
return devm_regmap_init_mmio(dev, regs, config);
}
/*
* Fall back to using REG and getting the resource from the parent
* device, which is possible in an MFD configuration
*/
if (dev->parent) {
res = platform_get_resource(pdev, IORESOURCE_REG, index);
if (!res)
return NULL;
return dev_get_regmap(dev->parent, res->name);
}
return NULL;
}
static inline struct regmap *
ocelot_regmap_from_resource(struct platform_device *pdev, unsigned int index,
const struct regmap_config *config)
{
struct regmap *map;
map = ocelot_regmap_from_resource_optional(pdev, index, config);
return map ?: ERR_PTR(-ENOENT);
}
#endif