mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-27 20:05:14 +07:00
d19d2de61f
Some gpio controllers ignores pin value writing when that pin is configured as input mode. As a result, bgpio_dir_out should set pin to output before configuring pin values or gpio pin values can't be set up properly. Introduce two variants of bgpio_dir_out: bgpio_dir_out_val_first and bgpio_dir_out_dir_first, and assign direction_output according to a new flag: BGPIOF_NO_SET_ON_INPUT. Signed-off-by: Chuanhong Guo <gch981213@gmail.com> Tested-by: René van Dorst <opensource@vdorst.com> Reviewed-by: Sergio Paracuellos <sergio.paracuellos@gmail.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
829 lines
21 KiB
C
829 lines
21 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* Generic driver for memory-mapped GPIO controllers.
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*
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* Copyright 2008 MontaVista Software, Inc.
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* Copyright 2008,2010 Anton Vorontsov <cbouatmailru@gmail.com>
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*
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* ....``.```~~~~````.`.`.`.`.```````'',,,.........`````......`.......
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* ...`` ```````..
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* ..The simplest form of a GPIO controller that the driver supports is``
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* `.just a single "data" register, where GPIO state can be read and/or `
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* `,..written. ,,..``~~~~ .....``.`.`.~~.```.`.........``````.```````
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* `````````
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___
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_/~~|___/~| . ```~~~~~~ ___/___\___ ,~.`.`.`.`````.~~...,,,,...
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__________|~$@~~~ %~ /o*o*o*o*o*o\ .. Implementing such a GPIO .
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o ` ~~~~\___/~~~~ ` controller in FPGA is ,.`
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`....trivial..'~`.```.```
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* ```````
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* .```````~~~~`..`.``.``.
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* . The driver supports `... ,..```.`~~~```````````````....````.``,,
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* . big-endian notation, just`. .. A bit more sophisticated controllers ,
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* . register the device with -be`. .with a pair of set/clear-bit registers ,
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* `.. suffix. ```~~`````....`.` . affecting the data register and the .`
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* ``.`.``...``` ```.. output pins are also supported.`
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* ^^ `````.`````````.,``~``~``~~``````
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* . ^^
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* ,..`.`.`...````````````......`.`.`.`.`.`..`.`.`..
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* .. The expectation is that in at least some cases . ,-~~~-,
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* .this will be used with roll-your-own ASIC/FPGA .` \ /
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* .logic in Verilog or VHDL. ~~~`````````..`````~~` \ /
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* ..````````......``````````` \o_
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* |
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* ^^ / \
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*
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* ...`````~~`.....``.`..........``````.`.``.```........``.
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* ` 8, 16, 32 and 64 bits registers are supported, and``.
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* . the number of GPIOs is determined by the width of ~
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* .. the registers. ,............```.`.`..`.`.~~~.`.`.`~
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* `.......````.```
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*/
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#include <linux/init.h>
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#include <linux/err.h>
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#include <linux/bug.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/spinlock.h>
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#include <linux/compiler.h>
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#include <linux/types.h>
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#include <linux/errno.h>
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#include <linux/log2.h>
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#include <linux/ioport.h>
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#include <linux/io.h>
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#include <linux/gpio/driver.h>
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#include <linux/slab.h>
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#include <linux/bitops.h>
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#include <linux/platform_device.h>
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#include <linux/mod_devicetable.h>
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#include <linux/of.h>
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#include <linux/of_device.h>
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static void bgpio_write8(void __iomem *reg, unsigned long data)
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{
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writeb(data, reg);
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}
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static unsigned long bgpio_read8(void __iomem *reg)
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{
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return readb(reg);
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}
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static void bgpio_write16(void __iomem *reg, unsigned long data)
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{
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writew(data, reg);
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}
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static unsigned long bgpio_read16(void __iomem *reg)
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{
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return readw(reg);
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}
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static void bgpio_write32(void __iomem *reg, unsigned long data)
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{
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writel(data, reg);
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}
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static unsigned long bgpio_read32(void __iomem *reg)
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{
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return readl(reg);
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}
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#if BITS_PER_LONG >= 64
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static void bgpio_write64(void __iomem *reg, unsigned long data)
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{
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writeq(data, reg);
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}
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static unsigned long bgpio_read64(void __iomem *reg)
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{
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return readq(reg);
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}
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#endif /* BITS_PER_LONG >= 64 */
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static void bgpio_write16be(void __iomem *reg, unsigned long data)
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{
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iowrite16be(data, reg);
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}
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static unsigned long bgpio_read16be(void __iomem *reg)
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{
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return ioread16be(reg);
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}
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static void bgpio_write32be(void __iomem *reg, unsigned long data)
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{
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iowrite32be(data, reg);
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}
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static unsigned long bgpio_read32be(void __iomem *reg)
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{
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return ioread32be(reg);
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}
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static unsigned long bgpio_line2mask(struct gpio_chip *gc, unsigned int line)
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{
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if (gc->be_bits)
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return BIT(gc->bgpio_bits - 1 - line);
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return BIT(line);
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}
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static int bgpio_get_set(struct gpio_chip *gc, unsigned int gpio)
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{
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unsigned long pinmask = bgpio_line2mask(gc, gpio);
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bool dir = !!(gc->bgpio_dir & pinmask);
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if (dir)
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return !!(gc->read_reg(gc->reg_set) & pinmask);
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else
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return !!(gc->read_reg(gc->reg_dat) & pinmask);
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}
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/*
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* This assumes that the bits in the GPIO register are in native endianness.
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* We only assign the function pointer if we have that.
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*/
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static int bgpio_get_set_multiple(struct gpio_chip *gc, unsigned long *mask,
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unsigned long *bits)
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{
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unsigned long get_mask = 0;
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unsigned long set_mask = 0;
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/* Make sure we first clear any bits that are zero when we read the register */
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*bits &= ~*mask;
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set_mask = *mask & gc->bgpio_dir;
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get_mask = *mask & ~gc->bgpio_dir;
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if (set_mask)
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*bits |= gc->read_reg(gc->reg_set) & set_mask;
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if (get_mask)
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*bits |= gc->read_reg(gc->reg_dat) & get_mask;
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return 0;
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}
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static int bgpio_get(struct gpio_chip *gc, unsigned int gpio)
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{
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return !!(gc->read_reg(gc->reg_dat) & bgpio_line2mask(gc, gpio));
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}
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/*
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* This only works if the bits in the GPIO register are in native endianness.
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*/
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static int bgpio_get_multiple(struct gpio_chip *gc, unsigned long *mask,
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unsigned long *bits)
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{
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/* Make sure we first clear any bits that are zero when we read the register */
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*bits &= ~*mask;
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*bits |= gc->read_reg(gc->reg_dat) & *mask;
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return 0;
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}
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/*
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* With big endian mirrored bit order it becomes more tedious.
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*/
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static int bgpio_get_multiple_be(struct gpio_chip *gc, unsigned long *mask,
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unsigned long *bits)
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{
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unsigned long readmask = 0;
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unsigned long val;
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int bit;
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/* Make sure we first clear any bits that are zero when we read the register */
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*bits &= ~*mask;
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/* Create a mirrored mask */
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bit = -1;
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while ((bit = find_next_bit(mask, gc->ngpio, bit + 1)) < gc->ngpio)
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readmask |= bgpio_line2mask(gc, bit);
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/* Read the register */
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val = gc->read_reg(gc->reg_dat) & readmask;
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/*
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* Mirror the result into the "bits" result, this will give line 0
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* in bit 0 ... line 31 in bit 31 for a 32bit register.
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*/
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bit = -1;
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while ((bit = find_next_bit(&val, gc->ngpio, bit + 1)) < gc->ngpio)
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*bits |= bgpio_line2mask(gc, bit);
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return 0;
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}
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static void bgpio_set_none(struct gpio_chip *gc, unsigned int gpio, int val)
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{
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}
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static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
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{
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unsigned long mask = bgpio_line2mask(gc, gpio);
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unsigned long flags;
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spin_lock_irqsave(&gc->bgpio_lock, flags);
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if (val)
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gc->bgpio_data |= mask;
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else
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gc->bgpio_data &= ~mask;
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gc->write_reg(gc->reg_dat, gc->bgpio_data);
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spin_unlock_irqrestore(&gc->bgpio_lock, flags);
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}
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static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio,
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int val)
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{
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unsigned long mask = bgpio_line2mask(gc, gpio);
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if (val)
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gc->write_reg(gc->reg_set, mask);
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else
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gc->write_reg(gc->reg_clr, mask);
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}
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static void bgpio_set_set(struct gpio_chip *gc, unsigned int gpio, int val)
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{
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unsigned long mask = bgpio_line2mask(gc, gpio);
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unsigned long flags;
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spin_lock_irqsave(&gc->bgpio_lock, flags);
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if (val)
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gc->bgpio_data |= mask;
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else
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gc->bgpio_data &= ~mask;
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gc->write_reg(gc->reg_set, gc->bgpio_data);
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spin_unlock_irqrestore(&gc->bgpio_lock, flags);
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}
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static void bgpio_multiple_get_masks(struct gpio_chip *gc,
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unsigned long *mask, unsigned long *bits,
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unsigned long *set_mask,
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unsigned long *clear_mask)
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{
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int i;
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*set_mask = 0;
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*clear_mask = 0;
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for (i = 0; i < gc->bgpio_bits; i++) {
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if (*mask == 0)
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break;
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if (__test_and_clear_bit(i, mask)) {
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if (test_bit(i, bits))
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*set_mask |= bgpio_line2mask(gc, i);
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else
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*clear_mask |= bgpio_line2mask(gc, i);
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}
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}
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}
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static void bgpio_set_multiple_single_reg(struct gpio_chip *gc,
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unsigned long *mask,
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unsigned long *bits,
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void __iomem *reg)
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{
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unsigned long flags;
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unsigned long set_mask, clear_mask;
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spin_lock_irqsave(&gc->bgpio_lock, flags);
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bgpio_multiple_get_masks(gc, mask, bits, &set_mask, &clear_mask);
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gc->bgpio_data |= set_mask;
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gc->bgpio_data &= ~clear_mask;
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gc->write_reg(reg, gc->bgpio_data);
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spin_unlock_irqrestore(&gc->bgpio_lock, flags);
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}
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static void bgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
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unsigned long *bits)
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{
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bgpio_set_multiple_single_reg(gc, mask, bits, gc->reg_dat);
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}
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static void bgpio_set_multiple_set(struct gpio_chip *gc, unsigned long *mask,
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unsigned long *bits)
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{
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bgpio_set_multiple_single_reg(gc, mask, bits, gc->reg_set);
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}
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static void bgpio_set_multiple_with_clear(struct gpio_chip *gc,
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unsigned long *mask,
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unsigned long *bits)
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{
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unsigned long set_mask, clear_mask;
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bgpio_multiple_get_masks(gc, mask, bits, &set_mask, &clear_mask);
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if (set_mask)
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gc->write_reg(gc->reg_set, set_mask);
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if (clear_mask)
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gc->write_reg(gc->reg_clr, clear_mask);
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}
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static int bgpio_simple_dir_in(struct gpio_chip *gc, unsigned int gpio)
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{
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return 0;
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}
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static int bgpio_dir_out_err(struct gpio_chip *gc, unsigned int gpio,
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int val)
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{
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return -EINVAL;
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}
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static int bgpio_simple_dir_out(struct gpio_chip *gc, unsigned int gpio,
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int val)
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{
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gc->set(gc, gpio, val);
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return 0;
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}
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static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
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{
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unsigned long flags;
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spin_lock_irqsave(&gc->bgpio_lock, flags);
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gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);
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if (gc->reg_dir_in)
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gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir);
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if (gc->reg_dir_out)
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gc->write_reg(gc->reg_dir_out, gc->bgpio_dir);
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spin_unlock_irqrestore(&gc->bgpio_lock, flags);
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return 0;
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}
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static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio)
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{
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/* Return 0 if output, 1 if input */
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if (gc->bgpio_dir_unreadable) {
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if (gc->bgpio_dir & bgpio_line2mask(gc, gpio))
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return GPIO_LINE_DIRECTION_OUT;
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return GPIO_LINE_DIRECTION_IN;
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}
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if (gc->reg_dir_out) {
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if (gc->read_reg(gc->reg_dir_out) & bgpio_line2mask(gc, gpio))
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return GPIO_LINE_DIRECTION_OUT;
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return GPIO_LINE_DIRECTION_IN;
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}
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if (gc->reg_dir_in)
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if (!(gc->read_reg(gc->reg_dir_in) & bgpio_line2mask(gc, gpio)))
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return GPIO_LINE_DIRECTION_OUT;
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return GPIO_LINE_DIRECTION_IN;
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}
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static void bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
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{
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unsigned long flags;
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spin_lock_irqsave(&gc->bgpio_lock, flags);
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gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
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if (gc->reg_dir_in)
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gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir);
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if (gc->reg_dir_out)
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gc->write_reg(gc->reg_dir_out, gc->bgpio_dir);
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spin_unlock_irqrestore(&gc->bgpio_lock, flags);
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}
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static int bgpio_dir_out_dir_first(struct gpio_chip *gc, unsigned int gpio,
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int val)
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{
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bgpio_dir_out(gc, gpio, val);
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gc->set(gc, gpio, val);
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return 0;
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}
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static int bgpio_dir_out_val_first(struct gpio_chip *gc, unsigned int gpio,
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int val)
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{
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gc->set(gc, gpio, val);
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bgpio_dir_out(gc, gpio, val);
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return 0;
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}
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static int bgpio_setup_accessors(struct device *dev,
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struct gpio_chip *gc,
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bool byte_be)
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{
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switch (gc->bgpio_bits) {
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case 8:
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gc->read_reg = bgpio_read8;
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gc->write_reg = bgpio_write8;
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break;
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case 16:
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if (byte_be) {
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gc->read_reg = bgpio_read16be;
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gc->write_reg = bgpio_write16be;
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} else {
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gc->read_reg = bgpio_read16;
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gc->write_reg = bgpio_write16;
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}
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break;
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case 32:
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if (byte_be) {
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gc->read_reg = bgpio_read32be;
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gc->write_reg = bgpio_write32be;
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} else {
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gc->read_reg = bgpio_read32;
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gc->write_reg = bgpio_write32;
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}
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break;
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#if BITS_PER_LONG >= 64
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case 64:
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if (byte_be) {
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dev_err(dev,
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"64 bit big endian byte order unsupported\n");
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return -EINVAL;
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} else {
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gc->read_reg = bgpio_read64;
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gc->write_reg = bgpio_write64;
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}
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break;
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#endif /* BITS_PER_LONG >= 64 */
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default:
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dev_err(dev, "unsupported data width %u bits\n", gc->bgpio_bits);
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return -EINVAL;
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}
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return 0;
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}
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/*
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* Create the device and allocate the resources. For setting GPIO's there are
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* three supported configurations:
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*
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* - single input/output register resource (named "dat").
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* - set/clear pair (named "set" and "clr").
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* - single output register resource and single input resource ("set" and
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* dat").
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*
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* For the single output register, this drives a 1 by setting a bit and a zero
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* by clearing a bit. For the set clr pair, this drives a 1 by setting a bit
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* in the set register and clears it by setting a bit in the clear register.
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* The configuration is detected by which resources are present.
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*
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* For setting the GPIO direction, there are three supported configurations:
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*
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* - simple bidirection GPIO that requires no configuration.
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* - an output direction register (named "dirout") where a 1 bit
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* indicates the GPIO is an output.
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* - an input direction register (named "dirin") where a 1 bit indicates
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* the GPIO is an input.
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*/
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static int bgpio_setup_io(struct gpio_chip *gc,
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void __iomem *dat,
|
|
void __iomem *set,
|
|
void __iomem *clr,
|
|
unsigned long flags)
|
|
{
|
|
|
|
gc->reg_dat = dat;
|
|
if (!gc->reg_dat)
|
|
return -EINVAL;
|
|
|
|
if (set && clr) {
|
|
gc->reg_set = set;
|
|
gc->reg_clr = clr;
|
|
gc->set = bgpio_set_with_clear;
|
|
gc->set_multiple = bgpio_set_multiple_with_clear;
|
|
} else if (set && !clr) {
|
|
gc->reg_set = set;
|
|
gc->set = bgpio_set_set;
|
|
gc->set_multiple = bgpio_set_multiple_set;
|
|
} else if (flags & BGPIOF_NO_OUTPUT) {
|
|
gc->set = bgpio_set_none;
|
|
gc->set_multiple = NULL;
|
|
} else {
|
|
gc->set = bgpio_set;
|
|
gc->set_multiple = bgpio_set_multiple;
|
|
}
|
|
|
|
if (!(flags & BGPIOF_UNREADABLE_REG_SET) &&
|
|
(flags & BGPIOF_READ_OUTPUT_REG_SET)) {
|
|
gc->get = bgpio_get_set;
|
|
if (!gc->be_bits)
|
|
gc->get_multiple = bgpio_get_set_multiple;
|
|
/*
|
|
* We deliberately avoid assigning the ->get_multiple() call
|
|
* for big endian mirrored registers which are ALSO reflecting
|
|
* their value in the set register when used as output. It is
|
|
* simply too much complexity, let the GPIO core fall back to
|
|
* reading each line individually in that fringe case.
|
|
*/
|
|
} else {
|
|
gc->get = bgpio_get;
|
|
if (gc->be_bits)
|
|
gc->get_multiple = bgpio_get_multiple_be;
|
|
else
|
|
gc->get_multiple = bgpio_get_multiple;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int bgpio_setup_direction(struct gpio_chip *gc,
|
|
void __iomem *dirout,
|
|
void __iomem *dirin,
|
|
unsigned long flags)
|
|
{
|
|
if (dirout || dirin) {
|
|
gc->reg_dir_out = dirout;
|
|
gc->reg_dir_in = dirin;
|
|
if (flags & BGPIOF_NO_SET_ON_INPUT)
|
|
gc->direction_output = bgpio_dir_out_dir_first;
|
|
else
|
|
gc->direction_output = bgpio_dir_out_val_first;
|
|
gc->direction_input = bgpio_dir_in;
|
|
gc->get_direction = bgpio_get_dir;
|
|
} else {
|
|
if (flags & BGPIOF_NO_OUTPUT)
|
|
gc->direction_output = bgpio_dir_out_err;
|
|
else
|
|
gc->direction_output = bgpio_simple_dir_out;
|
|
gc->direction_input = bgpio_simple_dir_in;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int bgpio_request(struct gpio_chip *chip, unsigned gpio_pin)
|
|
{
|
|
if (gpio_pin < chip->ngpio)
|
|
return 0;
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
/**
|
|
* bgpio_init() - Initialize generic GPIO accessor functions
|
|
* @gc: the GPIO chip to set up
|
|
* @dev: the parent device of the new GPIO chip (compulsory)
|
|
* @sz: the size (width) of the MMIO registers in bytes, typically 1, 2 or 4
|
|
* @dat: MMIO address for the register to READ the value of the GPIO lines, it
|
|
* is expected that a 1 in the corresponding bit in this register means the
|
|
* line is asserted
|
|
* @set: MMIO address for the register to SET the value of the GPIO lines, it is
|
|
* expected that we write the line with 1 in this register to drive the GPIO line
|
|
* high.
|
|
* @clr: MMIO address for the register to CLEAR the value of the GPIO lines, it is
|
|
* expected that we write the line with 1 in this register to drive the GPIO line
|
|
* low. It is allowed to leave this address as NULL, in that case the SET register
|
|
* will be assumed to also clear the GPIO lines, by actively writing the line
|
|
* with 0.
|
|
* @dirout: MMIO address for the register to set the line as OUTPUT. It is assumed
|
|
* that setting a line to 1 in this register will turn that line into an
|
|
* output line. Conversely, setting the line to 0 will turn that line into
|
|
* an input.
|
|
* @dirin: MMIO address for the register to set this line as INPUT. It is assumed
|
|
* that setting a line to 1 in this register will turn that line into an
|
|
* input line. Conversely, setting the line to 0 will turn that line into
|
|
* an output.
|
|
* @flags: Different flags that will affect the behaviour of the device, such as
|
|
* endianness etc.
|
|
*/
|
|
int bgpio_init(struct gpio_chip *gc, struct device *dev,
|
|
unsigned long sz, void __iomem *dat, void __iomem *set,
|
|
void __iomem *clr, void __iomem *dirout, void __iomem *dirin,
|
|
unsigned long flags)
|
|
{
|
|
int ret;
|
|
|
|
if (!is_power_of_2(sz))
|
|
return -EINVAL;
|
|
|
|
gc->bgpio_bits = sz * 8;
|
|
if (gc->bgpio_bits > BITS_PER_LONG)
|
|
return -EINVAL;
|
|
|
|
spin_lock_init(&gc->bgpio_lock);
|
|
gc->parent = dev;
|
|
gc->label = dev_name(dev);
|
|
gc->base = -1;
|
|
gc->ngpio = gc->bgpio_bits;
|
|
gc->request = bgpio_request;
|
|
gc->be_bits = !!(flags & BGPIOF_BIG_ENDIAN);
|
|
|
|
ret = bgpio_setup_io(gc, dat, set, clr, flags);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = bgpio_setup_accessors(dev, gc, flags & BGPIOF_BIG_ENDIAN_BYTE_ORDER);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = bgpio_setup_direction(gc, dirout, dirin, flags);
|
|
if (ret)
|
|
return ret;
|
|
|
|
gc->bgpio_data = gc->read_reg(gc->reg_dat);
|
|
if (gc->set == bgpio_set_set &&
|
|
!(flags & BGPIOF_UNREADABLE_REG_SET))
|
|
gc->bgpio_data = gc->read_reg(gc->reg_set);
|
|
|
|
if (flags & BGPIOF_UNREADABLE_REG_DIR)
|
|
gc->bgpio_dir_unreadable = true;
|
|
|
|
/*
|
|
* Inspect hardware to find initial direction setting.
|
|
*/
|
|
if ((gc->reg_dir_out || gc->reg_dir_in) &&
|
|
!(flags & BGPIOF_UNREADABLE_REG_DIR)) {
|
|
if (gc->reg_dir_out)
|
|
gc->bgpio_dir = gc->read_reg(gc->reg_dir_out);
|
|
else if (gc->reg_dir_in)
|
|
gc->bgpio_dir = ~gc->read_reg(gc->reg_dir_in);
|
|
/*
|
|
* If we have two direction registers, synchronise
|
|
* input setting to output setting, the library
|
|
* can not handle a line being input and output at
|
|
* the same time.
|
|
*/
|
|
if (gc->reg_dir_out && gc->reg_dir_in)
|
|
gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(bgpio_init);
|
|
|
|
#if IS_ENABLED(CONFIG_GPIO_GENERIC_PLATFORM)
|
|
|
|
static void __iomem *bgpio_map(struct platform_device *pdev,
|
|
const char *name,
|
|
resource_size_t sane_sz)
|
|
{
|
|
struct resource *r;
|
|
resource_size_t sz;
|
|
|
|
r = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
|
|
if (!r)
|
|
return NULL;
|
|
|
|
sz = resource_size(r);
|
|
if (sz != sane_sz)
|
|
return IOMEM_ERR_PTR(-EINVAL);
|
|
|
|
return devm_ioremap_resource(&pdev->dev, r);
|
|
}
|
|
|
|
#ifdef CONFIG_OF
|
|
static const struct of_device_id bgpio_of_match[] = {
|
|
{ .compatible = "brcm,bcm6345-gpio" },
|
|
{ .compatible = "wd,mbl-gpio" },
|
|
{ .compatible = "ni,169445-nand-gpio" },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, bgpio_of_match);
|
|
|
|
static struct bgpio_pdata *bgpio_parse_dt(struct platform_device *pdev,
|
|
unsigned long *flags)
|
|
{
|
|
struct bgpio_pdata *pdata;
|
|
|
|
if (!of_match_device(bgpio_of_match, &pdev->dev))
|
|
return NULL;
|
|
|
|
pdata = devm_kzalloc(&pdev->dev, sizeof(struct bgpio_pdata),
|
|
GFP_KERNEL);
|
|
if (!pdata)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
pdata->base = -1;
|
|
|
|
if (of_device_is_big_endian(pdev->dev.of_node))
|
|
*flags |= BGPIOF_BIG_ENDIAN_BYTE_ORDER;
|
|
|
|
if (of_property_read_bool(pdev->dev.of_node, "no-output"))
|
|
*flags |= BGPIOF_NO_OUTPUT;
|
|
|
|
return pdata;
|
|
}
|
|
#else
|
|
static struct bgpio_pdata *bgpio_parse_dt(struct platform_device *pdev,
|
|
unsigned long *flags)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif /* CONFIG_OF */
|
|
|
|
static int bgpio_pdev_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct resource *r;
|
|
void __iomem *dat;
|
|
void __iomem *set;
|
|
void __iomem *clr;
|
|
void __iomem *dirout;
|
|
void __iomem *dirin;
|
|
unsigned long sz;
|
|
unsigned long flags = 0;
|
|
int err;
|
|
struct gpio_chip *gc;
|
|
struct bgpio_pdata *pdata;
|
|
|
|
pdata = bgpio_parse_dt(pdev, &flags);
|
|
if (IS_ERR(pdata))
|
|
return PTR_ERR(pdata);
|
|
|
|
if (!pdata) {
|
|
pdata = dev_get_platdata(dev);
|
|
flags = pdev->id_entry->driver_data;
|
|
}
|
|
|
|
r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dat");
|
|
if (!r)
|
|
return -EINVAL;
|
|
|
|
sz = resource_size(r);
|
|
|
|
dat = bgpio_map(pdev, "dat", sz);
|
|
if (IS_ERR(dat))
|
|
return PTR_ERR(dat);
|
|
|
|
set = bgpio_map(pdev, "set", sz);
|
|
if (IS_ERR(set))
|
|
return PTR_ERR(set);
|
|
|
|
clr = bgpio_map(pdev, "clr", sz);
|
|
if (IS_ERR(clr))
|
|
return PTR_ERR(clr);
|
|
|
|
dirout = bgpio_map(pdev, "dirout", sz);
|
|
if (IS_ERR(dirout))
|
|
return PTR_ERR(dirout);
|
|
|
|
dirin = bgpio_map(pdev, "dirin", sz);
|
|
if (IS_ERR(dirin))
|
|
return PTR_ERR(dirin);
|
|
|
|
gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL);
|
|
if (!gc)
|
|
return -ENOMEM;
|
|
|
|
err = bgpio_init(gc, dev, sz, dat, set, clr, dirout, dirin, flags);
|
|
if (err)
|
|
return err;
|
|
|
|
if (pdata) {
|
|
if (pdata->label)
|
|
gc->label = pdata->label;
|
|
gc->base = pdata->base;
|
|
if (pdata->ngpio > 0)
|
|
gc->ngpio = pdata->ngpio;
|
|
}
|
|
|
|
platform_set_drvdata(pdev, gc);
|
|
|
|
return devm_gpiochip_add_data(&pdev->dev, gc, NULL);
|
|
}
|
|
|
|
static const struct platform_device_id bgpio_id_table[] = {
|
|
{
|
|
.name = "basic-mmio-gpio",
|
|
.driver_data = 0,
|
|
}, {
|
|
.name = "basic-mmio-gpio-be",
|
|
.driver_data = BGPIOF_BIG_ENDIAN,
|
|
},
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(platform, bgpio_id_table);
|
|
|
|
static struct platform_driver bgpio_driver = {
|
|
.driver = {
|
|
.name = "basic-mmio-gpio",
|
|
.of_match_table = of_match_ptr(bgpio_of_match),
|
|
},
|
|
.id_table = bgpio_id_table,
|
|
.probe = bgpio_pdev_probe,
|
|
};
|
|
|
|
module_platform_driver(bgpio_driver);
|
|
|
|
#endif /* CONFIG_GPIO_GENERIC_PLATFORM */
|
|
|
|
MODULE_DESCRIPTION("Driver for basic memory-mapped GPIO controllers");
|
|
MODULE_AUTHOR("Anton Vorontsov <cbouatmailru@gmail.com>");
|
|
MODULE_LICENSE("GPL");
|