freebsd-dev/sys/dev/sdhci/sdhci_fdt_gpio.c
2017-03-08 14:52:03 +00:00

267 lines
6.9 KiB
C

/*-
* Copyright (c) 2017 Ian Lepore <ian@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Support routines usable by any SoC sdhci bridge driver that uses gpio pins
* for card detect and write protect, and uses FDT data to describe those pins.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/gpio.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/taskqueue.h>
#include <dev/gpio/gpiobusvar.h>
#include <dev/mmc/bridge.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <dev/sdhci/sdhci.h>
#include <dev/sdhci/sdhci_fdt_gpio.h>
struct sdhci_fdt_gpio {
device_t dev;
struct sdhci_slot * slot;
gpio_pin_t wp_pin;
gpio_pin_t cd_pin;
void * cd_ihandler;
struct resource * cd_ires;
int cd_irid;
bool wp_disabled;
bool wp_inverted;
bool cd_disabled;
bool cd_inverted;
};
/*
* Card detect interrupt handler.
*/
static void
cd_intr(void *arg)
{
struct sdhci_fdt_gpio *gpio = arg;
sdhci_handle_card_present(gpio->slot, sdhci_fdt_gpio_get_present(gpio));
}
/*
* Card detect setup.
*/
static void
cd_setup(struct sdhci_fdt_gpio *gpio, phandle_t node)
{
int pincaps;
device_t dev;
const char *cd_mode_str;
dev = gpio->dev;
/*
* If the device is flagged as non-removable, set that slot option, and
* set a flag to make sdhci_fdt_gpio_get_present() always return true.
*/
if (OF_hasprop(node, "non-removable")) {
gpio->slot->opt |= SDHCI_NON_REMOVABLE;
gpio->cd_disabled = true;
if (bootverbose)
device_printf(dev, "Non-removable media\n");
return;
}
/*
* If there is no cd-gpios property, then presumably the hardware
* PRESENT_STATE register and interrupts will reflect card state
* properly, and there's nothing more for us to do. Our get_present()
* will return sdhci_generic_get_card_present() because cd_pin is NULL.
*
* If there is a property, make sure we can read the pin.
*/
if (gpio_pin_get_by_ofw_property(dev, node, "cd-gpios", &gpio->cd_pin))
return;
if (gpio_pin_getcaps(gpio->cd_pin, &pincaps) != 0 ||
!(pincaps & GPIO_PIN_INPUT)) {
device_printf(dev, "Cannot read card-detect gpio pin; "
"setting card-always-present flag.\n");
gpio->cd_disabled = true;
return;
}
if (OF_hasprop(node, "cd-inverted"))
gpio->cd_inverted = true;
/*
* If the pin can trigger an interrupt on both rising and falling edges,
* we can use it to detect card presence changes. If not, we'll request
* card presence polling instead of using interrupts.
*/
if (!(pincaps & GPIO_INTR_EDGE_BOTH)) {
if (bootverbose)
device_printf(dev, "Cannot configure "
"GPIO_INTR_EDGE_BOTH for card detect\n");
goto without_interrupts;
}
/*
* Create an interrupt resource from the pin and set up the interrupt.
*/
if ((gpio->cd_ires = gpio_alloc_intr_resource(dev, &gpio->cd_irid,
RF_ACTIVE, gpio->cd_pin, GPIO_INTR_EDGE_BOTH)) == NULL) {
if (bootverbose)
device_printf(dev, "Cannot allocate an IRQ for card "
"detect GPIO\n");
goto without_interrupts;
}
if (bus_setup_intr(dev, gpio->cd_ires, INTR_TYPE_BIO | INTR_MPSAFE,
NULL, cd_intr, gpio, &gpio->cd_ihandler) != 0) {
device_printf(dev, "Unable to setup card-detect irq handler\n");
gpio->cd_ihandler = NULL;
goto without_interrupts;
}
without_interrupts:
/*
* If we have a readable gpio pin, but didn't successfully configure
* gpio interrupts, ask the sdhci driver to poll from a callout.
*/
if (gpio->cd_ihandler == NULL) {
cd_mode_str = "polling";
gpio->slot->quirks |= SDHCI_QUIRK_POLL_CARD_PRESENT;
} else {
cd_mode_str = "interrupts";
}
if (bootverbose) {
device_printf(dev, "Card presence detect on %s pin %u, "
"configured for %s.\n",
device_get_nameunit(gpio->cd_pin->dev), gpio->cd_pin->pin,
cd_mode_str);
}
}
/*
* Write protect setup.
*/
static void
wp_setup(struct sdhci_fdt_gpio *gpio, phandle_t node)
{
device_t dev;
dev = gpio->dev;
if (OF_hasprop(node, "wp-disable")) {
gpio->wp_disabled = true;
if (bootverbose)
device_printf(dev, "Write protect disabled\n");
return;
}
if (gpio_pin_get_by_ofw_property(dev, node, "wp-gpios", &gpio->wp_pin))
return;
if (OF_hasprop(node, "wp-inverted"))
gpio->wp_inverted = true;
if (bootverbose)
device_printf(dev, "Write protect switch on %s pin %u\n",
device_get_nameunit(gpio->wp_pin->dev), gpio->wp_pin->pin);
}
struct sdhci_fdt_gpio *
sdhci_fdt_gpio_setup(device_t dev, struct sdhci_slot *slot)
{
phandle_t node;
struct sdhci_fdt_gpio *gpio;
gpio = malloc(sizeof(*gpio), M_DEVBUF, M_ZERO | M_WAITOK);
gpio->dev = dev;
gpio->slot = slot;
node = ofw_bus_get_node(dev);
wp_setup(gpio, node);
cd_setup(gpio, node);
return (gpio);
}
void
sdhci_fdt_gpio_teardown(struct sdhci_fdt_gpio *gpio)
{
if (gpio == NULL)
return;
if (gpio->cd_ihandler != NULL)
bus_teardown_intr(gpio->dev, gpio->cd_ires, gpio->cd_ihandler);
if (gpio->wp_pin != NULL)
gpio_pin_release(gpio->wp_pin);
if (gpio->cd_pin != NULL)
gpio_pin_release(gpio->cd_pin);
if (gpio->cd_ires != NULL)
bus_release_resource(gpio->dev, SYS_RES_IRQ, 0, gpio->cd_ires);
free(gpio, M_DEVBUF);
}
bool
sdhci_fdt_gpio_get_present(struct sdhci_fdt_gpio *gpio)
{
bool pinstate;
if (gpio->cd_disabled)
return (true);
if (gpio->cd_pin == NULL)
return (sdhci_generic_get_card_present(gpio->slot->bus,
gpio->slot));
gpio_pin_is_active(gpio->cd_pin, &pinstate);
return (pinstate ^ gpio->cd_inverted);
}
int
sdhci_fdt_gpio_get_readonly(struct sdhci_fdt_gpio *gpio)
{
bool pinstate;
if (gpio->wp_disabled)
return (false);
if (gpio->wp_pin == NULL)
return (sdhci_generic_get_ro(gpio->slot->bus, gpio->slot->dev));
gpio_pin_is_active(gpio->wp_pin, &pinstate);
return (pinstate ^ gpio->wp_inverted);
}