1 /*- 2 * Copyright (c) 2017 Ian Lepore <ian@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 /* 27 * Support routines usable by any SoC sdhci bridge driver that uses gpio pins 28 * for card detect and/or write protect, and uses FDT data to describe those 29 * pins. A bridge driver need only supply a couple 2-line forwarding functions 30 * to connect the get_present and get_readonly accessors to the corresponding 31 * driver interface functions, and add setup/teardown calls to its attach and 32 * detach functions. 33 */ 34 35 #ifndef _SDHCI_FDT_GPIO_H_ 36 #define _SDHCI_FDT_GPIO_H_ 37 38 struct sdhci_slot; 39 struct sdhci_fdt_gpio; 40 41 /* 42 * sdhci_fdt_gpio_setup() 43 * sdhci_fdt_gpio_teardown() 44 * 45 * Process FDT properties that use gpio pins and set up interrupt handling (if 46 * supported by hardware) and accessor functions to read the pins. 47 * 48 * Setup cannot fail. If the properties are not present, the accessors will 49 * return the values from standard sdhci registers. If the gpio controller 50 * can't trigger interrupts on both edges, it configures the slot to use polling 51 * for card presence detection. If it can't access the gpio pin at all it sets 52 * up the get_present() accessor to always return true. Likewise the 53 * get_readonly() accessor always returns false if its pin can't be accessed. 54 */ 55 struct sdhci_fdt_gpio *sdhci_fdt_gpio_setup(device_t dev, struct sdhci_slot *slot); 56 void sdhci_fdt_gpio_teardown(struct sdhci_fdt_gpio *gpio); 57 58 /* 59 * sdhci_fdt_gpio_get_present() 60 * sdhci_fdt_gpio_get_readonly() 61 * 62 * Gpio pin state accessor functions. 63 */ 64 bool sdhci_fdt_gpio_get_present(struct sdhci_fdt_gpio *gpio); 65 int sdhci_fdt_gpio_get_readonly(struct sdhci_fdt_gpio *gpio); 66 67 #endif 68