On Harmony board PCI-e subsystem can be enabled only after certain voltage regulators are on. One of the regulators is an internal regulator on the PMIC and another one is controlled by a PMIC GPIO. Addition of the voltage control to the Harmony PCI-e initialization allows booting of kernel with CONFIG_TEGRA_PCI even if the PMIC driver is not loaded. In this case the PCI-e initialization will fail gracefully intead of hanging the system.
Signed-off-by: Mike Rapoport <[email protected]> --- arch/arm/mach-tegra/board-harmony-pcie.c | 24 +++++++++++++++++++++++- 1 files changed, 23 insertions(+), 1 deletions(-) diff --git a/arch/arm/mach-tegra/board-harmony-pcie.c b/arch/arm/mach-tegra/board-harmony-pcie.c index f7e7d45..9c27b95 100644 --- a/arch/arm/mach-tegra/board-harmony-pcie.c +++ b/arch/arm/mach-tegra/board-harmony-pcie.c @@ -27,13 +27,29 @@ #ifdef CONFIG_TEGRA_PCI +/* GPIO 3 of the PMIC */ +#define EN_VDD_1V05_GPIO (TEGRA_NR_GPIOS + 2) + static int __init harmony_pcie_init(void) { + struct regulator *regulator = NULL; int err; if (!machine_is_harmony()) return 0; + err = gpio_request(EN_VDD_1V05_GPIO, "EN_VDD_1V05"); + if (err) + return err; + + gpio_direction_output(EN_VDD_1V05_GPIO, 1); + + regulator = regulator_get(NULL, "pex_clk"); + if (IS_ERR_OR_NULL(regulator)) + goto err_reg; + + regulator_enable(regulator); + tegra_pinmux_set_tristate(TEGRA_PINGROUP_GPV, TEGRA_TRI_NORMAL); tegra_pinmux_set_tristate(TEGRA_PINGROUP_SLXA, TEGRA_TRI_NORMAL); tegra_pinmux_set_tristate(TEGRA_PINGROUP_SLXK, TEGRA_TRI_NORMAL); @@ -49,9 +65,15 @@ err_pcie: tegra_pinmux_set_tristate(TEGRA_PINGROUP_SLXA, TEGRA_TRI_TRISTATE); tegra_pinmux_set_tristate(TEGRA_PINGROUP_SLXK, TEGRA_TRI_TRISTATE); + regulator_disable(regulator); + regulator_put(regulator); +err_reg: + gpio_free(EN_VDD_1V05_GPIO); + return err; } -subsys_initcall(harmony_pcie_init); +/* PCI should be initialized after I2C, mfd and regulators */ +subsys_initcall_sync(harmony_pcie_init); #endif -- 1.7.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
