linux/drivers/mfd/dm355evm_msp.c
Linus Torvalds 58cf279aca GPIO bulk updates for the v4.5 kernel cycle:
Infrastructural changes:
 
 - In struct gpio_chip, rename the .dev node to .parent to better reflect
   the fact that this is not the GPIO struct device abstraction. We will
   add that soon so this would be totallt confusing.
 
 - It was noted that the driver .get_value() callbacks was
   sometimes reporting negative -ERR values to the gpiolib core, expecting
   them to be propagated to consumer gpiod_get_value() and gpio_get_value()
   calls. This was not happening, so as there was a mess of drivers
   returning negative errors and some returning "anything else than zero"
   to indicate that a line was active. As some would have bit 31 set to
   indicate "line active" it clashed with negative error codes. This is
   fixed by the largeish series clamping values in all drivers with
   !!value to [0,1] and then augmenting the code to propagate error codes
   to consumers. (Includes some ACKed patches in other subsystems.)
 
 - Add a void *data pointer to struct gpio_chip. The container_of() design
   pattern is indeed very nice, but we want to reform the struct gpio_chip
   to be a non-volative, stateless business, and keep states internal to
   the gpiolib to be able to hold on to the state when adding a proper
   userspace ABI (character device) further down the road. To achieve this,
   drivers need a handle at the internal state that is not dependent on
   their struct gpio_chip() so we add gpiochip_add_data() and
   gpiochip_get_data() following the pattern of many other subsystems.
   All the "use gpiochip data pointer" patches transforms drivers to this
   scheme.
 
 - The Generic GPIO chip header has been merged into the general
   <linux/gpio/driver.h> header, and the custom header for that removed.
   Instead of having a separate mm_gpio_chip struct for these generic
   drivers, merge that into struct gpio_chip, simplifying the code and
   removing the need for separate and confusing includes.
 
 Misc improvements:
 
 - Stabilize the way GPIOs are looked up from the ACPI legacy
   specification.
 
 - Incremental driver features for PXA, PCA953X, Lantiq (patches from the
   OpenWRT community), RCAR, Zynq, PL061, 104-idi-48
 
 New drivers:
 
 - Add a GPIO chip to the ALSA SoC AC97 driver.
 
 - Add a new Broadcom NSP SoC driver (this lands in the pinctrl dir, but
   the branch is merged here too to account for infrastructural changes).
 
 - The sx150x driver now supports the sx1502.
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Merge tag 'gpio-v4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "Here is the bulk of GPIO changes for v4.5.

  Notably there are big refactorings mostly by myself, aimed at getting
  the gpio_chip into a shape that makes me believe I can proceed to
  preserve state for a proper userspace ABI (character device) that has
  already been proposed once, but resulted in the feedback that I need
  to go back and restructure stuff.  So I've been restructuring stuff.
  On the way I ran into brokenness (return code from the get_value()
  callback) and had to fix it.  Also, refactored generic GPIO to be
  simpler.

  Some of that is still waiting to trickle down from the subsystems all
  over the kernel that provide random gpio_chips, I've touched every
  single GPIO driver in the kernel now, oh man I didn't know I was
  responsible for so much...

  Apart from that we're churning along as usual.

  I took some effort to test and retest so it should merge nicely and we
  shook out a couple of bugs in -next.

  Infrastructural changes:

   - In struct gpio_chip, rename the .dev node to .parent to better
     reflect the fact that this is not the GPIO struct device
     abstraction.  We will add that soon so this would be totallt
     confusing.

   - It was noted that the driver .get_value() callbacks was sometimes
     reporting negative -ERR values to the gpiolib core, expecting them
     to be propagated to consumer gpiod_get_value() and gpio_get_value()
     calls.  This was not happening, so as there was a mess of drivers
     returning negative errors and some returning "anything else than
     zero" to indicate that a line was active.  As some would have bit
     31 set to indicate "line active" it clashed with negative error
     codes.  This is fixed by the largeish series clamping values in all
     drivers with !!value to [0,1] and then augmenting the code to
     propagate error codes to consumers.  (Includes some ACKed patches
     in other subsystems.)

   - Add a void *data pointer to struct gpio_chip.  The container_of()
     design pattern is indeed very nice, but we want to reform the
     struct gpio_chip to be a non-volative, stateless business, and keep
     states internal to the gpiolib to be able to hold on to the state
     when adding a proper userspace ABI (character device) further down
     the road.  To achieve this, drivers need a handle at the internal
     state that is not dependent on their struct gpio_chip() so we add
     gpiochip_add_data() and gpiochip_get_data() following the pattern
     of many other subsystems.  All the "use gpiochip data pointer"
     patches transforms drivers to this scheme.

   - The Generic GPIO chip header has been merged into the general
     <linux/gpio/driver.h> header, and the custom header for that
     removed.  Instead of having a separate mm_gpio_chip struct for
     these generic drivers, merge that into struct gpio_chip,
     simplifying the code and removing the need for separate and
     confusing includes.

  Misc improvements:

   - Stabilize the way GPIOs are looked up from the ACPI legacy
     specification.

   - Incremental driver features for PXA, PCA953X, Lantiq (patches from
     the OpenWRT community), RCAR, Zynq, PL061, 104-idi-48

  New drivers:

   - Add a GPIO chip to the ALSA SoC AC97 driver.

   - Add a new Broadcom NSP SoC driver (this lands in the pinctrl dir,
     but the branch is merged here too to account for infrastructural
     changes).

   - The sx150x driver now supports the sx1502"

* tag 'gpio-v4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (220 commits)
  gpio: generic: make bgpio_pdata always visible
  gpiolib: fix chip order in gpio list
  gpio: mpc8xxx: Do not use gpiochip_get_data() in mpc8xxx_gpio_save_regs()
  gpio: mm-lantiq: Do not use gpiochip_get_data() in ltq_mm_save_regs()
  gpio: brcmstb: Allow building driver for BMIPS_GENERIC
  gpio: brcmstb: Set endian flags for big-endian MIPS
  gpio: moxart: fix build regression
  gpio: xilinx: Do not use gpiochip_get_data() in xgpio_save_regs()
  leds: pca9532: use gpiochip data pointer
  leds: tca6507: use gpiochip data pointer
  hid: cp2112: use gpiochip data pointer
  bcma: gpio: use gpiochip data pointer
  avr32: gpio: use gpiochip data pointer
  video: fbdev: via: use gpiochip data pointer
  gpio: pch: Optimize pch_gpio_get()
  Revert "pinctrl: lantiq: Implement gpio_chip.to_irq"
  pinctrl: nsp-gpio: use gpiochip data pointer
  pinctrl: vt8500-wmt: use gpiochip data pointer
  pinctrl: exynos5440: use gpiochip data pointer
  pinctrl: at91-pio4: use gpiochip data pointer
  ...
2016-01-17 12:32:01 -08:00

438 lines
11 KiB
C

/*
* dm355evm_msp.c - driver for MSP430 firmware on DM355EVM board
*
* Copyright (C) 2008 David Brownell
*
* 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.
*/
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/leds.h>
#include <linux/i2c.h>
#include <linux/i2c/dm355evm_msp.h>
/*
* The DM355 is a DaVinci chip with video support but no C64+ DSP. Its
* EVM board has an MSP430 programmed with firmware for various board
* support functions. This driver exposes some of them directly, and
* supports other drivers (e.g. RTC, input) for more complex access.
*
* Because this firmware is entirely board-specific, this file embeds
* knowledge that would be passed as platform_data in a generic driver.
*
* This driver was tested with firmware revision A4.
*/
#if defined(CONFIG_INPUT_DM355EVM) || defined(CONFIG_INPUT_DM355EVM_MODULE)
#define msp_has_keyboard() true
#else
#define msp_has_keyboard() false
#endif
#if defined(CONFIG_LEDS_GPIO) || defined(CONFIG_LEDS_GPIO_MODULE)
#define msp_has_leds() true
#else
#define msp_has_leds() false
#endif
#if defined(CONFIG_RTC_DRV_DM355EVM) || defined(CONFIG_RTC_DRV_DM355EVM_MODULE)
#define msp_has_rtc() true
#else
#define msp_has_rtc() false
#endif
#if defined(CONFIG_VIDEO_TVP514X) || defined(CONFIG_VIDEO_TVP514X_MODULE)
#define msp_has_tvp() true
#else
#define msp_has_tvp() false
#endif
/*----------------------------------------------------------------------*/
/* REVISIT for paranoia's sake, retry reads/writes on error */
static struct i2c_client *msp430;
/**
* dm355evm_msp_write - Writes a register in dm355evm_msp
* @value: the value to be written
* @reg: register address
*
* Returns result of operation - 0 is success, else negative errno
*/
int dm355evm_msp_write(u8 value, u8 reg)
{
return i2c_smbus_write_byte_data(msp430, reg, value);
}
EXPORT_SYMBOL(dm355evm_msp_write);
/**
* dm355evm_msp_read - Reads a register from dm355evm_msp
* @reg: register address
*
* Returns result of operation - value, or negative errno
*/
int dm355evm_msp_read(u8 reg)
{
return i2c_smbus_read_byte_data(msp430, reg);
}
EXPORT_SYMBOL(dm355evm_msp_read);
/*----------------------------------------------------------------------*/
/*
* Many of the msp430 pins are just used as fixed-direction GPIOs.
* We could export a few more of them this way, if we wanted.
*/
#define MSP_GPIO(bit, reg) ((DM355EVM_MSP_ ## reg) << 3 | (bit))
static const u8 msp_gpios[] = {
/* eight leds */
MSP_GPIO(0, LED), MSP_GPIO(1, LED),
MSP_GPIO(2, LED), MSP_GPIO(3, LED),
MSP_GPIO(4, LED), MSP_GPIO(5, LED),
MSP_GPIO(6, LED), MSP_GPIO(7, LED),
/* SW6 and the NTSC/nPAL jumper */
MSP_GPIO(0, SWITCH1), MSP_GPIO(1, SWITCH1),
MSP_GPIO(2, SWITCH1), MSP_GPIO(3, SWITCH1),
MSP_GPIO(4, SWITCH1),
/* switches on MMC/SD sockets */
/*
* Note: EVMDM355_ECP_VA4.pdf suggests that Bit 2 and 4 should be
* checked for card detection. However on the EVM bit 1 and 3 gives
* this status, for 0 and 1 instance respectively. The pdf also
* suggests that Bit 1 and 3 should be checked for write protection.
* However on the EVM bit 2 and 4 gives this status,for 0 and 1
* instance respectively.
*/
MSP_GPIO(2, SDMMC), MSP_GPIO(1, SDMMC), /* mmc0 WP, nCD */
MSP_GPIO(4, SDMMC), MSP_GPIO(3, SDMMC), /* mmc1 WP, nCD */
};
#define MSP_GPIO_REG(offset) (msp_gpios[(offset)] >> 3)
#define MSP_GPIO_MASK(offset) BIT(msp_gpios[(offset)] & 0x07)
static int msp_gpio_in(struct gpio_chip *chip, unsigned offset)
{
switch (MSP_GPIO_REG(offset)) {
case DM355EVM_MSP_SWITCH1:
case DM355EVM_MSP_SWITCH2:
case DM355EVM_MSP_SDMMC:
return 0;
default:
return -EINVAL;
}
}
static u8 msp_led_cache;
static int msp_gpio_get(struct gpio_chip *chip, unsigned offset)
{
int reg, status;
reg = MSP_GPIO_REG(offset);
status = dm355evm_msp_read(reg);
if (status < 0)
return status;
if (reg == DM355EVM_MSP_LED)
msp_led_cache = status;
return !!(status & MSP_GPIO_MASK(offset));
}
static int msp_gpio_out(struct gpio_chip *chip, unsigned offset, int value)
{
int mask, bits;
/* NOTE: there are some other signals that could be
* packaged as output GPIOs, but they aren't as useful
* as the LEDs ... so for now we don't.
*/
if (MSP_GPIO_REG(offset) != DM355EVM_MSP_LED)
return -EINVAL;
mask = MSP_GPIO_MASK(offset);
bits = msp_led_cache;
bits &= ~mask;
if (value)
bits |= mask;
msp_led_cache = bits;
return dm355evm_msp_write(bits, DM355EVM_MSP_LED);
}
static void msp_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
msp_gpio_out(chip, offset, value);
}
static struct gpio_chip dm355evm_msp_gpio = {
.label = "dm355evm_msp",
.owner = THIS_MODULE,
.direction_input = msp_gpio_in,
.get = msp_gpio_get,
.direction_output = msp_gpio_out,
.set = msp_gpio_set,
.base = -EINVAL, /* dynamic assignment */
.ngpio = ARRAY_SIZE(msp_gpios),
.can_sleep = true,
};
/*----------------------------------------------------------------------*/
static struct device *add_child(struct i2c_client *client, const char *name,
void *pdata, unsigned pdata_len,
bool can_wakeup, int irq)
{
struct platform_device *pdev;
int status;
pdev = platform_device_alloc(name, -1);
if (!pdev) {
dev_dbg(&client->dev, "can't alloc dev\n");
status = -ENOMEM;
goto err;
}
device_init_wakeup(&pdev->dev, can_wakeup);
pdev->dev.parent = &client->dev;
if (pdata) {
status = platform_device_add_data(pdev, pdata, pdata_len);
if (status < 0) {
dev_dbg(&pdev->dev, "can't add platform_data\n");
goto err;
}
}
if (irq) {
struct resource r = {
.start = irq,
.flags = IORESOURCE_IRQ,
};
status = platform_device_add_resources(pdev, &r, 1);
if (status < 0) {
dev_dbg(&pdev->dev, "can't add irq\n");
goto err;
}
}
status = platform_device_add(pdev);
err:
if (status < 0) {
platform_device_put(pdev);
dev_err(&client->dev, "can't add %s dev\n", name);
return ERR_PTR(status);
}
return &pdev->dev;
}
static int add_children(struct i2c_client *client)
{
static const struct {
int offset;
char *label;
} config_inputs[] = {
/* 8 == right after the LEDs */
{ 8 + 0, "sw6_1", },
{ 8 + 1, "sw6_2", },
{ 8 + 2, "sw6_3", },
{ 8 + 3, "sw6_4", },
{ 8 + 4, "NTSC/nPAL", },
};
struct device *child;
int status;
int i;
/* GPIO-ish stuff */
dm355evm_msp_gpio.parent = &client->dev;
status = gpiochip_add(&dm355evm_msp_gpio);
if (status < 0)
return status;
/* LED output */
if (msp_has_leds()) {
#define GPIO_LED(l) .name = l, .active_low = true
static struct gpio_led evm_leds[] = {
{ GPIO_LED("dm355evm::ds14"),
.default_trigger = "heartbeat", },
{ GPIO_LED("dm355evm::ds15"),
.default_trigger = "mmc0", },
{ GPIO_LED("dm355evm::ds16"),
/* could also be a CE-ATA drive */
.default_trigger = "mmc1", },
{ GPIO_LED("dm355evm::ds17"),
.default_trigger = "nand-disk", },
{ GPIO_LED("dm355evm::ds18"), },
{ GPIO_LED("dm355evm::ds19"), },
{ GPIO_LED("dm355evm::ds20"), },
{ GPIO_LED("dm355evm::ds21"), },
};
#undef GPIO_LED
struct gpio_led_platform_data evm_led_data = {
.num_leds = ARRAY_SIZE(evm_leds),
.leds = evm_leds,
};
for (i = 0; i < ARRAY_SIZE(evm_leds); i++)
evm_leds[i].gpio = i + dm355evm_msp_gpio.base;
/* NOTE: these are the only fully programmable LEDs
* on the board, since GPIO-61/ds22 (and many signals
* going to DC7) must be used for AEMIF address lines
* unless the top 1 GB of NAND is unused...
*/
child = add_child(client, "leds-gpio",
&evm_led_data, sizeof(evm_led_data),
false, 0);
if (IS_ERR(child))
return PTR_ERR(child);
}
/* configuration inputs */
for (i = 0; i < ARRAY_SIZE(config_inputs); i++) {
int gpio = dm355evm_msp_gpio.base + config_inputs[i].offset;
gpio_request_one(gpio, GPIOF_IN, config_inputs[i].label);
/* make it easy for userspace to see these */
gpio_export(gpio, false);
}
/* MMC/SD inputs -- right after the last config input */
if (dev_get_platdata(&client->dev)) {
void (*mmcsd_setup)(unsigned) = dev_get_platdata(&client->dev);
mmcsd_setup(dm355evm_msp_gpio.base + 8 + 5);
}
/* RTC is a 32 bit counter, no alarm */
if (msp_has_rtc()) {
child = add_child(client, "rtc-dm355evm",
NULL, 0, false, 0);
if (IS_ERR(child))
return PTR_ERR(child);
}
/* input from buttons and IR remote (uses the IRQ) */
if (msp_has_keyboard()) {
child = add_child(client, "dm355evm_keys",
NULL, 0, true, client->irq);
if (IS_ERR(child))
return PTR_ERR(child);
}
return 0;
}
/*----------------------------------------------------------------------*/
static void dm355evm_command(unsigned command)
{
int status;
status = dm355evm_msp_write(command, DM355EVM_MSP_COMMAND);
if (status < 0)
dev_err(&msp430->dev, "command %d failure %d\n",
command, status);
}
static void dm355evm_power_off(void)
{
dm355evm_command(MSP_COMMAND_POWEROFF);
}
static int dm355evm_msp_remove(struct i2c_client *client)
{
pm_power_off = NULL;
msp430 = NULL;
return 0;
}
static int
dm355evm_msp_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
int status;
const char *video = msp_has_tvp() ? "TVP5146" : "imager";
if (msp430)
return -EBUSY;
msp430 = client;
/* display revision status; doubles as sanity check */
status = dm355evm_msp_read(DM355EVM_MSP_FIRMREV);
if (status < 0)
goto fail;
dev_info(&client->dev, "firmware v.%02X, %s as video-in\n",
status, video);
/* mux video input: either tvp5146 or some external imager */
status = dm355evm_msp_write(msp_has_tvp() ? 0 : MSP_VIDEO_IMAGER,
DM355EVM_MSP_VIDEO_IN);
if (status < 0)
dev_warn(&client->dev, "error %d muxing %s as video-in\n",
status, video);
/* init LED cache, and turn off the LEDs */
msp_led_cache = 0xff;
dm355evm_msp_write(msp_led_cache, DM355EVM_MSP_LED);
/* export capabilities we support */
status = add_children(client);
if (status < 0)
goto fail;
/* PM hookup */
pm_power_off = dm355evm_power_off;
return 0;
fail:
/* FIXME remove children ... */
dm355evm_msp_remove(client);
return status;
}
static const struct i2c_device_id dm355evm_msp_ids[] = {
{ "dm355evm_msp", 0 },
{ /* end of list */ },
};
MODULE_DEVICE_TABLE(i2c, dm355evm_msp_ids);
static struct i2c_driver dm355evm_msp_driver = {
.driver.name = "dm355evm_msp",
.id_table = dm355evm_msp_ids,
.probe = dm355evm_msp_probe,
.remove = dm355evm_msp_remove,
};
static int __init dm355evm_msp_init(void)
{
return i2c_add_driver(&dm355evm_msp_driver);
}
subsys_initcall(dm355evm_msp_init);
static void __exit dm355evm_msp_exit(void)
{
i2c_del_driver(&dm355evm_msp_driver);
}
module_exit(dm355evm_msp_exit);
MODULE_DESCRIPTION("Interface to MSP430 firmware on DM355EVM");
MODULE_LICENSE("GPL");