// SPDX-License-Identifier: GPL-2.0 /* * Mainly by David Woodhouse, somewhat modified by Jordan Crouse * * Copyright © 2006-2007 Red Hat, Inc. * Copyright © 2006-2007 Advanced Micro Devices, Inc. * Copyright © 2009 VIA Technology, Inc. * Copyright (c) 2010 Andres Salomon */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include "olpc_dcon.h" enum dcon_gpios { OLPC_DCON_STAT0, OLPC_DCON_STAT1, OLPC_DCON_IRQ, OLPC_DCON_LOAD, OLPC_DCON_BLANK, }; static const struct dcon_gpio gpios_asis[] = { [OLPC_DCON_STAT0] = { .name = "dcon_stat0", .flags = GPIOD_ASIS }, [OLPC_DCON_STAT1] = { .name = "dcon_stat1", .flags = GPIOD_ASIS }, [OLPC_DCON_IRQ] = { .name = "dcon_irq", .flags = GPIOD_ASIS }, [OLPC_DCON_LOAD] = { .name = "dcon_load", .flags = GPIOD_ASIS }, [OLPC_DCON_BLANK] = { .name = "dcon_blank", .flags = GPIOD_ASIS }, }; static struct gpio_desc *gpios[5]; static int dcon_init_xo_1(struct dcon_priv *dcon) { unsigned char lob; int ret, i; const struct dcon_gpio *pin = &gpios_asis[0]; for (i = 0; i < ARRAY_SIZE(gpios_asis); i++) { gpios[i] = devm_gpiod_get(&dcon->client->dev, pin[i].name, pin[i].flags); if (IS_ERR(gpios[i])) { ret = PTR_ERR(gpios[i]); pr_err("failed to request %s GPIO: %d\n", pin[i].name, ret); return ret; } } /* Turn off the event enable for GPIO7 just to be safe */ cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_EVENTS_ENABLE); /* * Determine the current state by reading the GPIO bit; earlier * stages of the boot process have established the state. * * Note that we read GPIO_OUTPUT_VAL rather than GPIO_READ_BACK here; * this is because OFW will disable input for the pin and set a value.. * READ_BACK will only contain a valid value if input is enabled and * then a value is set. So, future readings of the pin can use * READ_BACK, but the first one cannot. Awesome, huh? */ dcon->curr_src = cs5535_gpio_isset(OLPC_GPIO_DCON_LOAD, GPIO_OUTPUT_VAL) ? DCON_SOURCE_CPU : DCON_SOURCE_DCON; dcon->pending_src = dcon->curr_src; /* Set the directions for the GPIO pins */ gpiod_direction_input(gpios[OLPC_DCON_STAT0]); gpiod_direction_input(gpios[OLPC_DCON_STAT1]); gpiod_direction_input(gpios[OLPC_DCON_IRQ]); gpiod_direction_input(gpios[OLPC_DCON_BLANK]); gpiod_direction_output(gpios[OLPC_DCON_LOAD], dcon->curr_src == DCON_SOURCE_CPU); /* Set up the interrupt mappings */ /* Set the IRQ to pair 2 */ cs5535_gpio_setup_event(OLPC_GPIO_DCON_IRQ, 2, 0); /* Enable group 2 to trigger the DCON interrupt */ cs5535_gpio_set_irq(2, DCON_IRQ); /* Select edge level for interrupt (in PIC) */ lob = inb(0x4d0); lob &= ~(1 << DCON_IRQ); outb(lob, 0x4d0); /* Register the interrupt handler */ if (request_irq(DCON_IRQ, &dcon_interrupt, 0, "DCON", dcon)) { pr_err("failed to request DCON's irq\n"); return -EIO; } /* Clear INV_EN for GPIO7 (DCONIRQ) */ cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_INPUT_INVERT); /* Enable filter for GPIO12 (DCONBLANK) */ cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_INPUT_FILTER); /* Disable filter for GPIO7 */ cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_INPUT_FILTER); /* Disable event counter for GPIO7 (DCONIRQ) and GPIO12 (DCONBLANK) */ cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_INPUT_EVENT_COUNT); cs5535_gpio_clear(OLPC_GPIO_DCON_BLANK, GPIO_INPUT_EVENT_COUNT); /* Add GPIO12 to the Filter Event Pair #7 */ cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_FE7_SEL); /* Turn off negative Edge Enable for GPIO12 */ cs5535_gpio_clear(OLPC_GPIO_DCON_BLANK, GPIO_NEGATIVE_EDGE_EN); /* Enable negative Edge Enable for GPIO7 */ cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_NEGATIVE_EDGE_EN); /* Zero the filter amount for Filter Event Pair #7 */ cs5535_gpio_set(0, GPIO_FLTR7_AMOUNT); /* Clear the negative edge status for GPIO7 and GPIO12 */ cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_NEGATIVE_EDGE_STS); cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_NEGATIVE_EDGE_STS); /* FIXME: Clear the positive status as well, just to be sure */ cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_POSITIVE_EDGE_STS); cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_POSITIVE_EDGE_STS); /* Enable events for GPIO7 (DCONIRQ) and GPIO12 (DCONBLANK) */ cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_EVENTS_ENABLE); cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_EVENTS_ENABLE); return 0; } static void dcon_wiggle_xo_1(void) { int x; /* * According to HiMax, when powering the DCON up we should hold * SMB_DATA high for 8 SMB_CLK cycles. This will force the DCON * state machine to reset to a (sane) initial state. Mitch Bradley * did some testing and discovered that holding for 16 SMB_CLK cycles * worked a lot more reliably, so that's what we do here. * * According to the cs5536 spec, to set GPIO14 to SMB_CLK we must * simultaneously set AUX1 IN/OUT to GPIO14; ditto for SMB_DATA and * GPIO15. */ cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_VAL); cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_VAL); cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_ENABLE); cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_ENABLE); cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_AUX1); cs5535_gpio_clear(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_AUX1); cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_AUX2); cs5535_gpio_clear(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_AUX2); cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_INPUT_AUX1); cs5535_gpio_clear(OLPC_GPIO_SMB_DATA, GPIO_INPUT_AUX1); for (x = 0; x < 16; x++) { udelay(5); cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_VAL); udelay(5); cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_VAL); } udelay(5); cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_AUX1); cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_AUX1); cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_INPUT_AUX1); cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_INPUT_AUX1); } static void dcon_set_dconload_1(int val) { gpiod_set_value(gpios[OLPC_DCON_LOAD], val); } static int dcon_read_status_xo_1(u8 *status) { *status = gpiod_get_value(gpios[OLPC_DCON_STAT0]); *status |= gpiod_get_value(gpios[OLPC_DCON_STAT1]) << 1; /* Clear the negative edge status for GPIO7 */ cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_NEGATIVE_EDGE_STS); return 0; } struct dcon_platform_data dcon_pdata_xo_1 = { .init = dcon_init_xo_1, .bus_stabilize_wiggle = dcon_wiggle_xo_1, .set_dconload = dcon_set_dconload_1, .read_status = dcon_read_status_xo_1, };