1 /* 2 * linux/arch/arm/mach-pxa/mfp.c 3 * 4 * PXA3xx Multi-Function Pin Support 5 * 6 * Copyright (C) 2007 Marvell Internation Ltd. 7 * 8 * 2007-08-21: eric miao <eric.miao@marvell.com> 9 * initial version 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License version 2 as 13 * published by the Free Software Foundation. 14 */ 15 16 #include <linux/module.h> 17 #include <linux/kernel.h> 18 #include <linux/init.h> 19 #include <linux/io.h> 20 #include <linux/sysdev.h> 21 22 #include <mach/hardware.h> 23 #include <mach/mfp-pxa3xx.h> 24 #include <mach/pxa3xx-regs.h> 25 26 #ifdef CONFIG_PM 27 /* 28 * Configure the MFPs appropriately for suspend/resume. 29 * FIXME: this should probably depend on which system state we're 30 * entering - for instance, we might not want to place MFP pins in 31 * a pull-down mode if they're an active low chip select, and we're 32 * just entering standby. 33 */ 34 static int pxa3xx_mfp_suspend(struct sys_device *d, pm_message_t state) 35 { 36 mfp_config_lpm(); 37 return 0; 38 } 39 40 static int pxa3xx_mfp_resume(struct sys_device *d) 41 { 42 mfp_config_run(); 43 44 /* clear RDH bit when MFP settings are restored 45 * 46 * NOTE: the last 3 bits DxS are write-1-to-clear so carefully 47 * preserve them here in case they will be referenced later 48 */ 49 ASCR &= ~(ASCR_RDH | ASCR_D1S | ASCR_D2S | ASCR_D3S); 50 return 0; 51 } 52 #else 53 #define pxa3xx_mfp_suspend NULL 54 #define pxa3xx_mfp_resume NULL 55 #endif 56 57 struct sysdev_class pxa3xx_mfp_sysclass = { 58 .name = "mfp", 59 .suspend = pxa3xx_mfp_suspend, 60 .resume = pxa3xx_mfp_resume, 61 }; 62 63 static int __init mfp_init_devicefs(void) 64 { 65 if (cpu_is_pxa3xx()) 66 return sysdev_class_register(&pxa3xx_mfp_sysclass); 67 68 return 0; 69 } 70 postcore_initcall(mfp_init_devicefs); 71