From 9fb7070621bcc0cb7f2ab6ecc7a5b5490afb8aa4 Mon Sep 17 00:00:00 2001 From: br Date: Wed, 28 May 2014 06:11:12 +0000 Subject: Describe I2C arbitrator device in DTS and use it for Chromebook Snow only. Submitted by: Maxim Ignatenko --- sys/arm/samsung/exynos/chrome_ec.c | 59 +++++++++++++++++++++++++++++++------- 1 file changed, 48 insertions(+), 11 deletions(-) (limited to 'sys/arm') diff --git a/sys/arm/samsung/exynos/chrome_ec.c b/sys/arm/samsung/exynos/chrome_ec.c index 5ef64ee..7aa28bd 100644 --- a/sys/arm/samsung/exynos/chrome_ec.c +++ b/sys/arm/samsung/exynos/chrome_ec.c @@ -60,12 +60,11 @@ __FBSDID("$FreeBSD$"); #include -/* TODO: export to DTS */ -#define OUR_GPIO 177 -#define EC_GPIO 168 - struct ec_softc { device_t dev; + int have_arbitrator; + pcell_t our_gpio; + pcell_t ec_gpio; }; struct ec_softc *ec_sc; @@ -82,17 +81,24 @@ bus_claim(struct ec_softc *sc) device_t gpio_dev; int status; + if (sc->our_gpio == 0 || sc->ec_gpio == 0) { + device_printf(sc->dev, "i2c arbitrator is not configured\n"); + return (1); + } + gpio_dev = devclass_get_device(devclass_find("gpio"), 0); - if (gpio_dev == NULL) { + if (gpio_dev == NULL) { device_printf(sc->dev, "cant find gpio_dev\n"); return (1); } /* Say we want the bus */ - GPIO_PIN_SET(gpio_dev, OUR_GPIO, GPIO_PIN_LOW); + GPIO_PIN_SET(gpio_dev, sc->our_gpio, GPIO_PIN_LOW); + + /* TODO(imax): insert a delay to allow EC to react. */ /* Check EC decision */ - GPIO_PIN_GET(gpio_dev, EC_GPIO, &status); + GPIO_PIN_GET(gpio_dev, sc->ec_gpio, &status); if (status == 1) { /* Okay. We have bus */ @@ -108,13 +114,18 @@ bus_release(struct ec_softc *sc) { device_t gpio_dev; + if (sc->our_gpio == 0 || sc->ec_gpio == 0) { + device_printf(sc->dev, "i2c arbitrator is not configured\n"); + return (1); + } + gpio_dev = devclass_get_device(devclass_find("gpio"), 0); - if (gpio_dev == NULL) { + if (gpio_dev == NULL) { device_printf(sc->dev, "cant find gpio_dev\n"); return (1); } - GPIO_PIN_SET(gpio_dev, OUR_GPIO, GPIO_PIN_HIGH); + GPIO_PIN_SET(gpio_dev, sc->our_gpio, GPIO_PIN_HIGH); return (0); } @@ -209,6 +220,28 @@ int ec_hello(void) return (0); } +static void +configure_i2c_arbitrator(struct ec_softc *sc) +{ + phandle_t arbitrator; + + /* TODO(imax): look for compatible entry instead of hard-coded path */ + arbitrator = OF_finddevice("/i2c-arbitrator"); + if (arbitrator > 0 && + OF_hasprop(arbitrator, "freebsd,our-gpio") && + OF_hasprop(arbitrator, "freebsd,ec-gpio")) { + sc->have_arbitrator = 1; + OF_getencprop(arbitrator, "freebsd,our-gpio", + &sc->our_gpio, sizeof(sc->our_gpio)); + OF_getencprop(arbitrator, "freebsd,ec-gpio", + &sc->ec_gpio, sizeof(sc->ec_gpio)); + } else { + sc->have_arbitrator = 0; + sc->our_gpio = 0; + sc->ec_gpio = 0; + } +} + static int ec_attach(device_t dev) { @@ -219,6 +252,8 @@ ec_attach(device_t dev) ec_sc = sc; + configure_i2c_arbitrator(sc); + /* * Claim the bus. * @@ -227,7 +262,7 @@ ec_attach(device_t dev) * */ - if (bus_claim(sc) != 0) { + if (sc->have_arbitrator && bus_claim(sc) != 0) { return (ENXIO); } @@ -241,7 +276,9 @@ ec_detach(device_t dev) sc = device_get_softc(dev); - bus_release(sc); + if (sc->have_arbitrator) { + bus_release(sc); + } return (0); } -- cgit v1.1