/* * 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 * * This program is free software. You can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. */ #include #include #include #include #include "olpc_dcon.h" static int dcon_init_xo_1(struct dcon_priv *dcon) { unsigned char lob; if (gpio_request(OLPC_GPIO_DCON_STAT0, "OLPC-DCON")) { printk(KERN_ERR "olpc-dcon: failed to request STAT0 GPIO\n"); return -EIO; } if (gpio_request(OLPC_GPIO_DCON_STAT1, "OLPC-DCON")) { printk(KERN_ERR "olpc-dcon: failed to request STAT1 GPIO\n"); goto err_gp_stat1; } if (gpio_request(OLPC_GPIO_DCON_IRQ, "OLPC-DCON")) { printk(KERN_ERR "olpc-dcon: failed to request IRQ GPIO\n"); goto err_gp_irq; } if (gpio_request(OLPC_GPIO_DCON_LOAD, "OLPC-DCON")) { printk(KERN_ERR "olpc-dcon: failed to request LOAD GPIO\n"); goto err_gp_load; } if (gpio_request(OLPC_GPIO_DCON_BLANK, "OLPC-DCON")) { printk(KERN_ERR "olpc-dcon: failed to request BLANK GPIO\n"); goto err_gp_blank; } /* 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_OUPUT_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 */ gpio_direction_input(OLPC_GPIO_DCON_STAT0); gpio_direction_input(OLPC_GPIO_DCON_STAT1); gpio_direction_input(OLPC_GPIO_DCON_IRQ); gpio_direction_input(OLPC_GPIO_DCON_BLANK); gpio_direction_output(OLPC_GPIO_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)) { printk(KERN_ERR "olpc-dcon: failed to request DCON's irq\n"); goto err_req_irq; } /* 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 posiitive 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; err_req_irq: gpio_free(OLPC_GPIO_DCON_BLANK); err_gp_blank: gpio_free(OLPC_GPIO_DCON_LOAD); err_gp_load: gpio_free(OLPC_GPIO_DCON_IRQ); err_gp_irq: gpio_free(OLPC_GPIO_DCON_STAT1); err_gp_stat1: gpio_free(OLPC_GPIO_DCON_STAT0); return -EIO; } 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) { gpio_set_value(OLPC_GPIO_DCON_LOAD, val); } static int dcon_read_status_xo_1(u8 *status) { *status = gpio_get_value(OLPC_GPIO_DCON_STAT0); *status |= gpio_get_value(OLPC_GPIO_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, };