Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile
Linus Torvalds [Wed, 3 Aug 2011 07:16:11 +0000 (21:16 -1000)]
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  arch/tile/mm/init.c: trivial: use BUG_ON
  arch/tile: remove useless set_fixmap_nocache() macro
  arch/tile: add hypervisor-based character driver for SPI flash ROM
  ioctl-number.txt: add the tile hardwall ioctl range
  tile: use generic-y format for one-line asm-generic headers
  clocksource: tile: convert to use clocksource_register_hz

46 files changed:
Documentation/ioctl/ioctl-number.txt
arch/tile/include/asm/Kbuild
arch/tile/include/asm/bug.h [deleted file]
arch/tile/include/asm/bugs.h [deleted file]
arch/tile/include/asm/cputime.h [deleted file]
arch/tile/include/asm/device.h [deleted file]
arch/tile/include/asm/div64.h [deleted file]
arch/tile/include/asm/emergency-restart.h [deleted file]
arch/tile/include/asm/errno.h [deleted file]
arch/tile/include/asm/fb.h [deleted file]
arch/tile/include/asm/fcntl.h [deleted file]
arch/tile/include/asm/fixmap.h
arch/tile/include/asm/ioctl.h [deleted file]
arch/tile/include/asm/ioctls.h [deleted file]
arch/tile/include/asm/ipc.h [deleted file]
arch/tile/include/asm/ipcbuf.h [deleted file]
arch/tile/include/asm/irq_regs.h [deleted file]
arch/tile/include/asm/kdebug.h [deleted file]
arch/tile/include/asm/local.h [deleted file]
arch/tile/include/asm/module.h [deleted file]
arch/tile/include/asm/msgbuf.h [deleted file]
arch/tile/include/asm/mutex.h [deleted file]
arch/tile/include/asm/param.h [deleted file]
arch/tile/include/asm/parport.h [deleted file]
arch/tile/include/asm/poll.h [deleted file]
arch/tile/include/asm/posix_types.h [deleted file]
arch/tile/include/asm/resource.h [deleted file]
arch/tile/include/asm/scatterlist.h [deleted file]
arch/tile/include/asm/sembuf.h [deleted file]
arch/tile/include/asm/serial.h [deleted file]
arch/tile/include/asm/shmbuf.h [deleted file]
arch/tile/include/asm/shmparam.h [deleted file]
arch/tile/include/asm/socket.h [deleted file]
arch/tile/include/asm/sockios.h [deleted file]
arch/tile/include/asm/statfs.h [deleted file]
arch/tile/include/asm/termbits.h [deleted file]
arch/tile/include/asm/termios.h [deleted file]
arch/tile/include/asm/types.h [deleted file]
arch/tile/include/asm/ucontext.h [deleted file]
arch/tile/include/asm/xor.h [deleted file]
arch/tile/include/hv/drv_srom_intf.h [new file with mode: 0644]
arch/tile/kernel/time.c
arch/tile/mm/init.c
drivers/char/Kconfig
drivers/char/Makefile
drivers/char/tile-srom.c [new file with mode: 0644]

index 72ba8d5..845a191 100644 (file)
@@ -292,6 +292,7 @@ Code  Seq#(hex)     Include File            Comments
                                        <mailto:buk@buks.ipn.de>
 0xA0   all     linux/sdp/sdp.h         Industrial Device Project
                                        <mailto:kenji@bitgate.com>
+0xA2   00-0F   arch/tile/include/asm/hardwall.h
 0xA3   80-8F   Port ACL                in development:
                                        <mailto:tlewis@mindspring.com>
 0xA3   90-9F   linux/dtlk.h
index 849ab2f..aec60dc 100644 (file)
@@ -2,3 +2,41 @@ include include/asm-generic/Kbuild.asm
 
 header-y += ucontext.h
 header-y += hardwall.h
+
+generic-y += bug.h
+generic-y += bugs.h
+generic-y += cputime.h
+generic-y += device.h
+generic-y += div64.h
+generic-y += emergency-restart.h
+generic-y += errno.h
+generic-y += fb.h
+generic-y += fcntl.h
+generic-y += ioctl.h
+generic-y += ioctls.h
+generic-y += ipc.h
+generic-y += ipcbuf.h
+generic-y += irq_regs.h
+generic-y += kdebug.h
+generic-y += local.h
+generic-y += module.h
+generic-y += msgbuf.h
+generic-y += mutex.h
+generic-y += param.h
+generic-y += parport.h
+generic-y += poll.h
+generic-y += posix_types.h
+generic-y += resource.h
+generic-y += scatterlist.h
+generic-y += sembuf.h
+generic-y += serial.h
+generic-y += shmbuf.h
+generic-y += shmparam.h
+generic-y += socket.h
+generic-y += sockios.h
+generic-y += statfs.h
+generic-y += termbits.h
+generic-y += termios.h
+generic-y += types.h
+generic-y += ucontext.h
+generic-y += xor.h
diff --git a/arch/tile/include/asm/bug.h b/arch/tile/include/asm/bug.h
deleted file mode 100644 (file)
index b12fd89..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/bug.h>
diff --git a/arch/tile/include/asm/bugs.h b/arch/tile/include/asm/bugs.h
deleted file mode 100644 (file)
index 61791e1..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/bugs.h>
diff --git a/arch/tile/include/asm/cputime.h b/arch/tile/include/asm/cputime.h
deleted file mode 100644 (file)
index 6d68ad7..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/cputime.h>
diff --git a/arch/tile/include/asm/device.h b/arch/tile/include/asm/device.h
deleted file mode 100644 (file)
index f0a4c25..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/device.h>
diff --git a/arch/tile/include/asm/div64.h b/arch/tile/include/asm/div64.h
deleted file mode 100644 (file)
index 6cd978c..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/div64.h>
diff --git a/arch/tile/include/asm/emergency-restart.h b/arch/tile/include/asm/emergency-restart.h
deleted file mode 100644 (file)
index 3711bd9..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/emergency-restart.h>
diff --git a/arch/tile/include/asm/errno.h b/arch/tile/include/asm/errno.h
deleted file mode 100644 (file)
index 4c82b50..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/errno.h>
diff --git a/arch/tile/include/asm/fb.h b/arch/tile/include/asm/fb.h
deleted file mode 100644 (file)
index 3a4988e..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/fb.h>
diff --git a/arch/tile/include/asm/fcntl.h b/arch/tile/include/asm/fcntl.h
deleted file mode 100644 (file)
index 46ab12d..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/fcntl.h>
index 51537ff..c66f793 100644 (file)
@@ -75,12 +75,6 @@ extern void __set_fixmap(enum fixed_addresses idx,
 
 #define set_fixmap(idx, phys) \
                __set_fixmap(idx, phys, PAGE_KERNEL)
-/*
- * Some hardware wants to get fixmapped without caching.
- */
-#define set_fixmap_nocache(idx, phys) \
-               __set_fixmap(idx, phys, PAGE_KERNEL_NOCACHE)
-
 #define clear_fixmap(idx) \
                __set_fixmap(idx, 0, __pgprot(0))
 
diff --git a/arch/tile/include/asm/ioctl.h b/arch/tile/include/asm/ioctl.h
deleted file mode 100644 (file)
index b279fe0..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/ioctl.h>
diff --git a/arch/tile/include/asm/ioctls.h b/arch/tile/include/asm/ioctls.h
deleted file mode 100644 (file)
index ec34c76..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/ioctls.h>
diff --git a/arch/tile/include/asm/ipc.h b/arch/tile/include/asm/ipc.h
deleted file mode 100644 (file)
index a46e3d9..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/ipc.h>
diff --git a/arch/tile/include/asm/ipcbuf.h b/arch/tile/include/asm/ipcbuf.h
deleted file mode 100644 (file)
index 84c7e51..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/ipcbuf.h>
diff --git a/arch/tile/include/asm/irq_regs.h b/arch/tile/include/asm/irq_regs.h
deleted file mode 100644 (file)
index 3dd9c0b..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/irq_regs.h>
diff --git a/arch/tile/include/asm/kdebug.h b/arch/tile/include/asm/kdebug.h
deleted file mode 100644 (file)
index 6ece1b0..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/kdebug.h>
diff --git a/arch/tile/include/asm/local.h b/arch/tile/include/asm/local.h
deleted file mode 100644 (file)
index c11c530..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/local.h>
diff --git a/arch/tile/include/asm/module.h b/arch/tile/include/asm/module.h
deleted file mode 100644 (file)
index 1e4b79f..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/module.h>
diff --git a/arch/tile/include/asm/msgbuf.h b/arch/tile/include/asm/msgbuf.h
deleted file mode 100644 (file)
index 809134c..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/msgbuf.h>
diff --git a/arch/tile/include/asm/mutex.h b/arch/tile/include/asm/mutex.h
deleted file mode 100644 (file)
index ff6101a..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/mutex-dec.h>
diff --git a/arch/tile/include/asm/param.h b/arch/tile/include/asm/param.h
deleted file mode 100644 (file)
index 965d454..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/param.h>
diff --git a/arch/tile/include/asm/parport.h b/arch/tile/include/asm/parport.h
deleted file mode 100644 (file)
index cf252af..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/parport.h>
diff --git a/arch/tile/include/asm/poll.h b/arch/tile/include/asm/poll.h
deleted file mode 100644 (file)
index c98509d..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/poll.h>
diff --git a/arch/tile/include/asm/posix_types.h b/arch/tile/include/asm/posix_types.h
deleted file mode 100644 (file)
index 22cae62..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/posix_types.h>
diff --git a/arch/tile/include/asm/resource.h b/arch/tile/include/asm/resource.h
deleted file mode 100644 (file)
index 04bc4db..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/resource.h>
diff --git a/arch/tile/include/asm/scatterlist.h b/arch/tile/include/asm/scatterlist.h
deleted file mode 100644 (file)
index 35d786f..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/scatterlist.h>
diff --git a/arch/tile/include/asm/sembuf.h b/arch/tile/include/asm/sembuf.h
deleted file mode 100644 (file)
index 7673b83..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/sembuf.h>
diff --git a/arch/tile/include/asm/serial.h b/arch/tile/include/asm/serial.h
deleted file mode 100644 (file)
index a0cb0ca..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/serial.h>
diff --git a/arch/tile/include/asm/shmbuf.h b/arch/tile/include/asm/shmbuf.h
deleted file mode 100644 (file)
index 83c05fc..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/shmbuf.h>
diff --git a/arch/tile/include/asm/shmparam.h b/arch/tile/include/asm/shmparam.h
deleted file mode 100644 (file)
index 93f30de..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/shmparam.h>
diff --git a/arch/tile/include/asm/socket.h b/arch/tile/include/asm/socket.h
deleted file mode 100644 (file)
index 6b71384..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/socket.h>
diff --git a/arch/tile/include/asm/sockios.h b/arch/tile/include/asm/sockios.h
deleted file mode 100644 (file)
index def6d47..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/sockios.h>
diff --git a/arch/tile/include/asm/statfs.h b/arch/tile/include/asm/statfs.h
deleted file mode 100644 (file)
index 0b91fe1..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/statfs.h>
diff --git a/arch/tile/include/asm/termbits.h b/arch/tile/include/asm/termbits.h
deleted file mode 100644 (file)
index 3935b10..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/termbits.h>
diff --git a/arch/tile/include/asm/termios.h b/arch/tile/include/asm/termios.h
deleted file mode 100644 (file)
index 280d78a..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/termios.h>
diff --git a/arch/tile/include/asm/types.h b/arch/tile/include/asm/types.h
deleted file mode 100644 (file)
index b9e79bc..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/types.h>
diff --git a/arch/tile/include/asm/ucontext.h b/arch/tile/include/asm/ucontext.h
deleted file mode 100644 (file)
index 9bc07b9..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/ucontext.h>
diff --git a/arch/tile/include/asm/xor.h b/arch/tile/include/asm/xor.h
deleted file mode 100644 (file)
index c82eb12..0000000
+++ /dev/null
@@ -1 +0,0 @@
-#include <asm-generic/xor.h>
diff --git a/arch/tile/include/hv/drv_srom_intf.h b/arch/tile/include/hv/drv_srom_intf.h
new file mode 100644 (file)
index 0000000..6395faa
--- /dev/null
@@ -0,0 +1,41 @@
+/*
+ * Copyright 2011 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+/**
+ * @file drv_srom_intf.h
+ * Interface definitions for the SPI Flash ROM driver.
+ */
+
+#ifndef _SYS_HV_INCLUDE_DRV_SROM_INTF_H
+#define _SYS_HV_INCLUDE_DRV_SROM_INTF_H
+
+/** Read this offset to get the total device size. */
+#define SROM_TOTAL_SIZE_OFF   0xF0000000
+
+/** Read this offset to get the device sector size. */
+#define SROM_SECTOR_SIZE_OFF  0xF0000004
+
+/** Read this offset to get the device page size. */
+#define SROM_PAGE_SIZE_OFF    0xF0000008
+
+/** Write this offset to flush any pending writes. */
+#define SROM_FLUSH_OFF        0xF1000000
+
+/** Write this offset, plus the byte offset of the start of a sector, to
+ *  erase a sector.  Any write data is ignored, but there must be at least
+ *  one byte of write data.  Only applies when the driver is in MTD mode.
+ */
+#define SROM_ERASE_OFF        0xF2000000
+
+#endif /* _SYS_HV_INCLUDE_DRV_SROM_INTF_H */
index c4be58c..f6f50f2 100644 (file)
@@ -78,7 +78,6 @@ static struct clocksource cycle_counter_cs = {
        .rating = 300,
        .read = clocksource_get_cycles,
        .mask = CLOCKSOURCE_MASK(64),
-       .shift = 22,   /* typical value, e.g. x86 tsc uses this */
        .flags = CLOCK_SOURCE_IS_CONTINUOUS,
 };
 
@@ -91,8 +90,6 @@ void __init setup_clock(void)
        cycles_per_sec = hv_sysconf(HV_SYSCONF_CPU_SPEED);
        sched_clock_mult =
                clocksource_hz2mult(cycles_per_sec, SCHED_CLOCK_SHIFT);
-       cycle_counter_cs.mult =
-               clocksource_hz2mult(cycles_per_sec, cycle_counter_cs.shift);
 }
 
 void __init calibrate_delay(void)
@@ -107,7 +104,7 @@ void __init calibrate_delay(void)
 void __init time_init(void)
 {
        /* Initialize and register the clock source. */
-       clocksource_register(&cycle_counter_cs);
+       clocksource_register_hz(&cycle_counter_cs, cycles_per_sec);
 
        /* Start up the tile-timer interrupt source on the boot cpu. */
        setup_tile_timer();
index 4e10c40..7309988 100644 (file)
@@ -836,8 +836,7 @@ void __init mem_init(void)
 #endif
 
 #ifdef CONFIG_FLATMEM
-       if (!mem_map)
-               BUG();
+       BUG_ON(!mem_map);
 #endif
 
 #ifdef CONFIG_HIGHMEM
index 49502bc..423fd56 100644 (file)
@@ -616,5 +616,16 @@ config MSM_SMD_PKT
          Enables userspace clients to read and write to some packet SMD
          ports via device interface for MSM chipset.
 
+config TILE_SROM
+       bool "Character-device access via hypervisor to the Tilera SPI ROM"
+       depends on TILE
+       default y
+       ---help---
+         This device provides character-level read-write access
+         to the SROM, typically via the "0", "1", and "2" devices
+         in /dev/srom/.  The Tilera hypervisor makes the flash
+         device appear much like a simple EEPROM, and knows
+         how to partition a single ROM for multiple purposes.
+
 endmenu
 
index 7a00672..32762ba 100644 (file)
@@ -63,3 +63,5 @@ obj-$(CONFIG_RAMOOPS)         += ramoops.o
 
 obj-$(CONFIG_JS_RTC)           += js-rtc.o
 js-rtc-y = rtc.o
+
+obj-$(CONFIG_TILE_SROM)                += tile-srom.o
diff --git a/drivers/char/tile-srom.c b/drivers/char/tile-srom.c
new file mode 100644 (file)
index 0000000..cf3ee00
--- /dev/null
@@ -0,0 +1,481 @@
+/*
+ * Copyright 2011 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ *
+ * SPI Flash ROM driver
+ *
+ * This source code is derived from code provided in "Linux Device
+ * Drivers, Third Edition", by Jonathan Corbet, Alessandro Rubini, and
+ * Greg Kroah-Hartman, published by O'Reilly Media, Inc.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/kernel.h>      /* printk() */
+#include <linux/slab.h>                /* kmalloc() */
+#include <linux/fs.h>          /* everything... */
+#include <linux/errno.h>       /* error codes */
+#include <linux/types.h>       /* size_t */
+#include <linux/proc_fs.h>
+#include <linux/fcntl.h>       /* O_ACCMODE */
+#include <linux/aio.h>
+#include <linux/pagemap.h>
+#include <linux/hugetlb.h>
+#include <linux/uaccess.h>
+#include <linux/platform_device.h>
+#include <hv/hypervisor.h>
+#include <linux/ioctl.h>
+#include <linux/cdev.h>
+#include <linux/delay.h>
+#include <hv/drv_srom_intf.h>
+
+/*
+ * Size of our hypervisor I/O requests.  We break up large transfers
+ * so that we don't spend large uninterrupted spans of time in the
+ * hypervisor.  Erasing an SROM sector takes a significant fraction of
+ * a second, so if we allowed the user to, say, do one I/O to write the
+ * entire ROM, we'd get soft lockup timeouts, or worse.
+ */
+#define SROM_CHUNK_SIZE ((size_t)4096)
+
+/*
+ * When hypervisor is busy (e.g. erasing), poll the status periodically.
+ */
+
+/*
+ * Interval to poll the state in msec
+ */
+#define SROM_WAIT_TRY_INTERVAL 20
+
+/*
+ * Maximum times to poll the state
+ */
+#define SROM_MAX_WAIT_TRY_TIMES 1000
+
+struct srom_dev {
+       int hv_devhdl;                  /* Handle for hypervisor device */
+       u32 total_size;                 /* Size of this device */
+       u32 sector_size;                /* Size of a sector */
+       u32 page_size;                  /* Size of a page */
+       struct mutex lock;              /* Allow only one accessor at a time */
+};
+
+static int srom_major;                 /* Dynamic major by default */
+module_param(srom_major, int, 0);
+MODULE_AUTHOR("Tilera Corporation");
+MODULE_LICENSE("GPL");
+
+static int srom_devs;                  /* Number of SROM partitions */
+static struct cdev srom_cdev;
+static struct class *srom_class;
+static struct srom_dev *srom_devices;
+
+/*
+ * Handle calling the hypervisor and managing EAGAIN/EBUSY.
+ */
+
+static ssize_t _srom_read(int hv_devhdl, void *buf,
+                         loff_t off, size_t count)
+{
+       int retval, retries = SROM_MAX_WAIT_TRY_TIMES;
+       for (;;) {
+               retval = hv_dev_pread(hv_devhdl, 0, (HV_VirtAddr)buf,
+                                     count, off);
+               if (retval >= 0)
+                       return retval;
+               if (retval == HV_EAGAIN)
+                       continue;
+               if (retval == HV_EBUSY && --retries > 0) {
+                       msleep(SROM_WAIT_TRY_INTERVAL);
+                       continue;
+               }
+               pr_err("_srom_read: error %d\n", retval);
+               return -EIO;
+       }
+}
+
+static ssize_t _srom_write(int hv_devhdl, const void *buf,
+                          loff_t off, size_t count)
+{
+       int retval, retries = SROM_MAX_WAIT_TRY_TIMES;
+       for (;;) {
+               retval = hv_dev_pwrite(hv_devhdl, 0, (HV_VirtAddr)buf,
+                                      count, off);
+               if (retval >= 0)
+                       return retval;
+               if (retval == HV_EAGAIN)
+                       continue;
+               if (retval == HV_EBUSY && --retries > 0) {
+                       msleep(SROM_WAIT_TRY_INTERVAL);
+                       continue;
+               }
+               pr_err("_srom_write: error %d\n", retval);
+               return -EIO;
+       }
+}
+
+/**
+ * srom_open() - Device open routine.
+ * @inode: Inode for this device.
+ * @filp: File for this specific open of the device.
+ *
+ * Returns zero, or an error code.
+ */
+static int srom_open(struct inode *inode, struct file *filp)
+{
+       filp->private_data = &srom_devices[iminor(inode)];
+       return 0;
+}
+
+
+/**
+ * srom_release() - Device release routine.
+ * @inode: Inode for this device.
+ * @filp: File for this specific open of the device.
+ *
+ * Returns zero, or an error code.
+ */
+static int srom_release(struct inode *inode, struct file *filp)
+{
+       struct srom_dev *srom = filp->private_data;
+       char dummy;
+
+       /* Make sure we've flushed anything written to the ROM. */
+       mutex_lock(&srom->lock);
+       if (srom->hv_devhdl >= 0)
+               _srom_write(srom->hv_devhdl, &dummy, SROM_FLUSH_OFF, 1);
+       mutex_unlock(&srom->lock);
+
+       filp->private_data = NULL;
+
+       return 0;
+}
+
+
+/**
+ * srom_read() - Read data from the device.
+ * @filp: File for this specific open of the device.
+ * @buf: User's data buffer.
+ * @count: Number of bytes requested.
+ * @f_pos: File position.
+ *
+ * Returns number of bytes read, or an error code.
+ */
+static ssize_t srom_read(struct file *filp, char __user *buf,
+                        size_t count, loff_t *f_pos)
+{
+       int retval = 0;
+       void *kernbuf;
+       struct srom_dev *srom = filp->private_data;
+
+       kernbuf = kmalloc(SROM_CHUNK_SIZE, GFP_KERNEL);
+       if (!kernbuf)
+               return -ENOMEM;
+
+       if (mutex_lock_interruptible(&srom->lock)) {
+               retval = -ERESTARTSYS;
+               kfree(kernbuf);
+               return retval;
+       }
+
+       while (count) {
+               int hv_retval;
+               int bytes_this_pass = min(count, SROM_CHUNK_SIZE);
+
+               hv_retval = _srom_read(srom->hv_devhdl, kernbuf,
+                                      *f_pos, bytes_this_pass);
+               if (hv_retval > 0) {
+                       if (copy_to_user(buf, kernbuf, hv_retval) != 0) {
+                               retval = -EFAULT;
+                               break;
+                       }
+               } else if (hv_retval <= 0) {
+                       if (retval == 0)
+                               retval = hv_retval;
+                       break;
+               }
+
+               retval += hv_retval;
+               *f_pos += hv_retval;
+               buf += hv_retval;
+               count -= hv_retval;
+       }
+
+       mutex_unlock(&srom->lock);
+       kfree(kernbuf);
+
+       return retval;
+}
+
+/**
+ * srom_write() - Write data to the device.
+ * @filp: File for this specific open of the device.
+ * @buf: User's data buffer.
+ * @count: Number of bytes requested.
+ * @f_pos: File position.
+ *
+ * Returns number of bytes written, or an error code.
+ */
+static ssize_t srom_write(struct file *filp, const char __user *buf,
+                         size_t count, loff_t *f_pos)
+{
+       int retval = 0;
+       void *kernbuf;
+       struct srom_dev *srom = filp->private_data;
+
+       kernbuf = kmalloc(SROM_CHUNK_SIZE, GFP_KERNEL);
+       if (!kernbuf)
+               return -ENOMEM;
+
+       if (mutex_lock_interruptible(&srom->lock)) {
+               retval = -ERESTARTSYS;
+               kfree(kernbuf);
+               return retval;
+       }
+
+       while (count) {
+               int hv_retval;
+               int bytes_this_pass = min(count, SROM_CHUNK_SIZE);
+
+               if (copy_from_user(kernbuf, buf, bytes_this_pass) != 0) {
+                       retval = -EFAULT;
+                       break;
+               }
+
+               hv_retval = _srom_write(srom->hv_devhdl, kernbuf,
+                                       *f_pos, bytes_this_pass);
+               if (hv_retval <= 0) {
+                       if (retval == 0)
+                               retval = hv_retval;
+                       break;
+               }
+
+               retval += hv_retval;
+               *f_pos += hv_retval;
+               buf += hv_retval;
+               count -= hv_retval;
+       }
+
+       mutex_unlock(&srom->lock);
+       kfree(kernbuf);
+
+       return retval;
+}
+
+/* Provide our own implementation so we can use srom->total_size. */
+loff_t srom_llseek(struct file *filp, loff_t offset, int origin)
+{
+       struct srom_dev *srom = filp->private_data;
+
+       if (mutex_lock_interruptible(&srom->lock))
+               return -ERESTARTSYS;
+
+       switch (origin) {
+       case SEEK_END:
+               offset += srom->total_size;
+               break;
+       case SEEK_CUR:
+               offset += filp->f_pos;
+               break;
+       }
+
+       if (offset < 0 || offset > srom->total_size) {
+               offset = -EINVAL;
+       } else {
+               filp->f_pos = offset;
+               filp->f_version = 0;
+       }
+
+       mutex_unlock(&srom->lock);
+
+       return offset;
+}
+
+static ssize_t total_show(struct device *dev,
+                         struct device_attribute *attr, char *buf)
+{
+       struct srom_dev *srom = dev_get_drvdata(dev);
+       return sprintf(buf, "%u\n", srom->total_size);
+}
+
+static ssize_t sector_show(struct device *dev,
+                          struct device_attribute *attr, char *buf)
+{
+       struct srom_dev *srom = dev_get_drvdata(dev);
+       return sprintf(buf, "%u\n", srom->sector_size);
+}
+
+static ssize_t page_show(struct device *dev,
+                        struct device_attribute *attr, char *buf)
+{
+       struct srom_dev *srom = dev_get_drvdata(dev);
+       return sprintf(buf, "%u\n", srom->page_size);
+}
+
+static struct device_attribute srom_dev_attrs[] = {
+       __ATTR(total_size, S_IRUGO, total_show, NULL),
+       __ATTR(sector_size, S_IRUGO, sector_show, NULL),
+       __ATTR(page_size, S_IRUGO, page_show, NULL),
+       __ATTR_NULL
+};
+
+static char *srom_devnode(struct device *dev, mode_t *mode)
+{
+       *mode = S_IRUGO | S_IWUSR;
+       return kasprintf(GFP_KERNEL, "srom/%s", dev_name(dev));
+}
+
+/*
+ * The fops
+ */
+static const struct file_operations srom_fops = {
+       .owner =     THIS_MODULE,
+       .llseek =    srom_llseek,
+       .read =      srom_read,
+       .write =     srom_write,
+       .open =      srom_open,
+       .release =   srom_release,
+};
+
+/**
+ * srom_setup_minor() - Initialize per-minor information.
+ * @srom: Per-device SROM state.
+ * @index: Device to set up.
+ */
+static int srom_setup_minor(struct srom_dev *srom, int index)
+{
+       struct device *dev;
+       int devhdl = srom->hv_devhdl;
+
+       mutex_init(&srom->lock);
+
+       if (_srom_read(devhdl, &srom->total_size,
+                      SROM_TOTAL_SIZE_OFF, sizeof(srom->total_size)) < 0)
+               return -EIO;
+       if (_srom_read(devhdl, &srom->sector_size,
+                      SROM_SECTOR_SIZE_OFF, sizeof(srom->sector_size)) < 0)
+               return -EIO;
+       if (_srom_read(devhdl, &srom->page_size,
+                      SROM_PAGE_SIZE_OFF, sizeof(srom->page_size)) < 0)
+               return -EIO;
+
+       dev = device_create(srom_class, &platform_bus,
+                           MKDEV(srom_major, index), srom, "%d", index);
+       return IS_ERR(dev) ? PTR_ERR(dev) : 0;
+}
+
+/** srom_init() - Initialize the driver's module. */
+static int srom_init(void)
+{
+       int result, i;
+       dev_t dev = MKDEV(srom_major, 0);
+
+       /*
+        * Start with a plausible number of partitions; the krealloc() call
+        * below will yield about log(srom_devs) additional allocations.
+        */
+       srom_devices = kzalloc(4 * sizeof(struct srom_dev), GFP_KERNEL);
+
+       /* Discover the number of srom partitions. */
+       for (i = 0; ; i++) {
+               int devhdl;
+               char buf[20];
+               struct srom_dev *new_srom_devices =
+                       krealloc(srom_devices, (i+1) * sizeof(struct srom_dev),
+                                GFP_KERNEL | __GFP_ZERO);
+               if (!new_srom_devices) {
+                       result = -ENOMEM;
+                       goto fail_mem;
+               }
+               srom_devices = new_srom_devices;
+               sprintf(buf, "srom/0/%d", i);
+               devhdl = hv_dev_open((HV_VirtAddr)buf, 0);
+               if (devhdl < 0) {
+                       if (devhdl != HV_ENODEV)
+                               pr_notice("srom/%d: hv_dev_open failed: %d.\n",
+                                         i, devhdl);
+                       break;
+               }
+               srom_devices[i].hv_devhdl = devhdl;
+       }
+       srom_devs = i;
+
+       /* Bail out early if we have no partitions at all. */
+       if (srom_devs == 0) {
+               result = -ENODEV;
+               goto fail_mem;
+       }
+
+       /* Register our major, and accept a dynamic number. */
+       if (srom_major)
+               result = register_chrdev_region(dev, srom_devs, "srom");
+       else {
+               result = alloc_chrdev_region(&dev, 0, srom_devs, "srom");
+               srom_major = MAJOR(dev);
+       }
+       if (result < 0)
+               goto fail_mem;
+
+       /* Register a character device. */
+       cdev_init(&srom_cdev, &srom_fops);
+       srom_cdev.owner = THIS_MODULE;
+       srom_cdev.ops = &srom_fops;
+       result = cdev_add(&srom_cdev, dev, srom_devs);
+       if (result < 0)
+               goto fail_chrdev;
+
+       /* Create a sysfs class. */
+       srom_class = class_create(THIS_MODULE, "srom");
+       if (IS_ERR(srom_class)) {
+               result = PTR_ERR(srom_class);
+               goto fail_cdev;
+       }
+       srom_class->dev_attrs = srom_dev_attrs;
+       srom_class->devnode = srom_devnode;
+
+       /* Do per-partition initialization */
+       for (i = 0; i < srom_devs; i++) {
+               result = srom_setup_minor(srom_devices + i, i);
+               if (result < 0)
+                       goto fail_class;
+       }
+
+       return 0;
+
+fail_class:
+       for (i = 0; i < srom_devs; i++)
+               device_destroy(srom_class, MKDEV(srom_major, i));
+       class_destroy(srom_class);
+fail_cdev:
+       cdev_del(&srom_cdev);
+fail_chrdev:
+       unregister_chrdev_region(dev, srom_devs);
+fail_mem:
+       kfree(srom_devices);
+       return result;
+}
+
+/** srom_cleanup() - Clean up the driver's module. */
+static void srom_cleanup(void)
+{
+       int i;
+       for (i = 0; i < srom_devs; i++)
+               device_destroy(srom_class, MKDEV(srom_major, i));
+       class_destroy(srom_class);
+       cdev_del(&srom_cdev);
+       unregister_chrdev_region(MKDEV(srom_major, 0), srom_devs);
+       kfree(srom_devices);
+}
+
+module_init(srom_init);
+module_exit(srom_cleanup);