+++ /dev/null
-/*
- * Greybus endo code
- *
- * Copyright 2014-2015 Google Inc.
- * Copyright 2014-2015 Linaro Ltd.
- *
- * Released under the GPLv2 only.
- */
-
-#include "greybus.h"
-
-/* Endo ID (16 bits long) Masks */
-#define ENDO_ID_MASK 0xFFFF
-#define ENDO_LARGE_MASK 0x1000
-#define ENDO_MEDIUM_MASK 0x0400
-#define ENDO_MINI_MASK 0x0100
-
-#define ENDO_FRONT_MASK(id) ((id) >> 13)
-#define ENDO_BACK_SIDE_RIBS_MASK(ribs) ((1 << (ribs)) - 1)
-
-/*
- * endo_is_medium() should be used only if endo isn't large. And endo_is_mini()
- * should be used only if endo isn't large or medium.
- */
-#define endo_is_large(id) ((id) & ENDO_LARGE_MASK)
-#define endo_is_medium(id) ((id) & ENDO_MEDIUM_MASK)
-#define endo_is_mini(id) ((id) & ENDO_MINI_MASK)
-
-#define endo_back_left_ribs(id, ribs) (((id) >> (ribs)) & ENDO_BACK_SIDE_RIBS_MASK(ribs))
-#define endo_back_right_ribs(id, ribs) ((id) & ENDO_BACK_SIDE_RIBS_MASK(ribs))
-
-/*
- * An Endo has interface block positions on the front and back.
- * Each has numeric ID, starting with 1 (interface 0 represents
- * the SVC within the Endo itself). The maximum interface ID is the
- * also the number of non-SVC interfaces possible on the endo.
- *
- * Total number of interfaces:
- * - Front: 4
- * - Back left: max_ribs + 1
- * - Back right: max_ribs + 1
- */
-#define max_endo_interface_id(endo_layout) \
- (4 + ((endo_layout)->max_ribs + 1) * 2)
-
-static struct ida greybus_endo_id_map;
-
-/* endo sysfs attributes */
-static ssize_t serial_number_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct gb_endo *endo = to_gb_endo(dev);
-
- return sprintf(buf, "%s\n", &endo->svc_info.serial_number[0]);
-}
-static DEVICE_ATTR_RO(serial_number);
-
-static ssize_t version_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct gb_endo *endo = to_gb_endo(dev);
-
- return sprintf(buf, "%s\n", &endo->svc_info.version[0]);
-}
-static DEVICE_ATTR_RO(version);
-
-static struct attribute *svc_attrs[] = {
- &dev_attr_serial_number.attr,
- &dev_attr_version.attr,
- NULL,
-};
-
-static const struct attribute_group svc_group = {
- .attrs = svc_attrs,
- .name = "svc",
-};
-
-static const struct attribute_group *endo_groups[] = {
- &svc_group,
- NULL,
-};
-
-static void gb_endo_release(struct device *dev)
-{
- struct gb_endo *endo = to_gb_endo(dev);
-
- ida_simple_remove(&greybus_endo_id_map, endo->dev_id);
- kfree(endo);
-}
-
-struct device_type greybus_endo_type = {
- .name = "greybus_endo",
- .release = gb_endo_release,
-};
-
-
-/* Validate Endo ID */
-
-/*
- * The maximum module height is 2 units. This means any adjacent pair of bits
- * in the left or right mask must have at least one bit set.
- */
-static inline bool modules_oversized(unsigned int count, unsigned int mask)
-{
- int i;
-
- for (i = 0; i < count - 1; i++)
- if (!(mask & (0x3 << i)))
- return true;
-
- return false;
-}
-
-/* Reverse a number of least significant bits in a value */
-static u8 reverse_bits(unsigned int value, unsigned int bits)
-{
- u8 result = 0;
- u8 result_mask = 1 << (bits - 1);
- u8 value_mask = 1;
-
- while (value && result_mask) {
- if (value & value_mask) {
- result |= result_mask;
- value ^= value_mask;
- }
- value_mask <<= 1;
- result_mask >>= 1;
- }
-
- return result;
-}
-
-/*
- * An Endo can have at most one instance of a single rib spanning its whole
- * width. That is, the left and right bit masks representing the rib positions
- * must have at most one bit set in both masks.
- */
-static bool single_cross_rib(u8 left_ribs, u8 right_ribs)
-{
- u8 span_ribs = left_ribs & right_ribs;
-
- /* Power of 2 ? */
- if (span_ribs & (span_ribs - 1))
- return false;
- return true;
-}
-
-/*
- * Each Endo size has its own set of front module configurations. For most, the
- * resulting rib mask is the same regardless of the Endo size. The mini Endo
- * has a few differences though.
- *
- * Endo front has 4 interface blocks and 3 rib positions. A maximum of 2 ribs
- * are allowed to be present for any endo type.
- *
- * This routine validates front mask and sets 'front_ribs', its 3 least
- * significant bits represent front ribs mask, other are 0. The front values
- * should be within range (1..6).
- *
- * front_ribs bitmask:
- * - Bit 0: 1st rib location from top, i.e. between interface 1 and 2.
- * - Bit 1: 2nd rib location from top, i.e. between interface 2 and 3.
- * - Bit 2: 3rd rib location from top, i.e. between interface 3 and 4.
- */
-static bool validate_front_ribs(struct gb_host_device *hd,
- struct endo_layout *layout, bool mini,
- u16 endo_id)
-{
- u8 front_mask = ENDO_FRONT_MASK(endo_id);
-
- /* Verify front endo mask is in valid range, i.e. 1-6 */
-
- switch (front_mask) {
- case 1:
- layout->front_ribs = 0x0;
- break;
- case 2:
- layout->front_ribs = 0x1;
- break;
- case 3:
- layout->front_ribs = 0x4;
- break;
- case 4:
- layout->front_ribs = mini ? 0x2 : 0x3;
- break;
- case 5:
- layout->front_ribs = mini ? 0x2 : 0x6;
- break;
- case 6:
- layout->front_ribs = 0x5;
- break;
- default:
- dev_err(&hd->dev,
- "%s: Invalid endo front mask 0x%02x, id 0x%04x\n",
- __func__, front_mask, endo_id);
- return false;
- }
-
- return true;
-}
-
-/*
- * The rear of an endo has a single vertical "spine", and the modules placed on
- * the left and right of that spine are separated by ribs. Only one "cross"
- * (i.e. rib that spans the entire width) is allowed of the back of the endo;
- * all other ribs reach from the spine to the left or right edge.
- *
- * The width of the module positions on the left and right of the spine are
- * determined by the width of the endo (either 1 or 2 "units"). The height of
- * the modules is determined by the placement of the ribs (a module can be
- * either 1 or 2 units high).
- *
- * The lower 13 bits of the 16-bit endo id are used to encode back ribs
- * information. The large form factor endo uses all of these bits; the medium
- * and mini form factors leave some bits unused (such bits shall be ignored, and
- * are 0 for the purposes of this endo id definition).
- *
- * Each defined bit represents a rib position on one or the other side
- * of the spine on the back of an endo. If that bit is set (1), it
- * means a rib is present in the corresponding location; otherwise
- * there is no rib there.
- *
- * Rotating an endo 180 degrees does not produce a new rib configuration. A
- * single endo id represents a specific configuration of ribs without regard to
- * its rotational orientation. We define one canonical id to represent a
- * particular endo configuration.
- */
-static bool validate_back_ribs(struct gb_host_device *hd,
- struct endo_layout *layout, u16 endo_id)
-{
- u8 max_ribs = layout->max_ribs;
- u8 left_ribs;
- u8 right_ribs;
-
- /* Extract the left and right rib masks */
- left_ribs = endo_back_left_ribs(endo_id, max_ribs);
- right_ribs = endo_back_right_ribs(endo_id, max_ribs);
-
- if (!single_cross_rib(left_ribs, right_ribs)) {
- dev_err(&hd->dev,
- "%s: More than one spanning rib (left 0x%02x right 0x%02x), id 0x%04x\n",
- __func__, left_ribs, right_ribs, endo_id);
- return false;
- }
-
- if (modules_oversized(max_ribs, left_ribs)) {
- dev_err(&hd->dev,
- "%s: Oversized module (left) 0x%02x, id 0x%04x\n",
- __func__, left_ribs, endo_id);
- return false;
- }
-
- if (modules_oversized(max_ribs, right_ribs)) {
- dev_err(&hd->dev,
- "%s: Oversized module (Right) 0x%02x, id 0x%04x\n",
- __func__, right_ribs, endo_id);
- return false;
- }
-
- /*
- * The Endo numbering scheme represents the left and right rib
- * configuration in a way that's convenient for looking for multiple
- * spanning ribs. But it doesn't match the normal Endo interface
- * numbering scheme (increasing counter-clockwise around the back).
- * Reverse the right bit positions so they do match.
- */
- right_ribs = reverse_bits(right_ribs, max_ribs);
-
- /*
- * A mini or large Endo rotated 180 degrees is still the same Endo. In
- * most cases that allows two distinct values to represent the same
- * Endo; we choose one of them to be the canonical one (and the other is
- * invalid). The canonical one is identified by higher value of left
- * ribs mask.
- *
- * This doesn't apply to medium Endos, because the left and right sides
- * are of different widths.
- */
- if (max_ribs != ENDO_BACK_RIBS_MEDIUM && left_ribs < right_ribs) {
- dev_err(&hd->dev, "%s: Non-canonical endo id 0x%04x\n", __func__,
- endo_id);
- return false;
- }
-
- layout->left_ribs = left_ribs;
- layout->right_ribs = right_ribs;
- return true;
-}
-
-/*
- * Validate the endo-id passed from SVC. Error out if its not a valid Endo,
- * else return structure representing ribs positions on front and back of Endo.
- */
-static int gb_endo_validate_id(struct gb_host_device *hd,
- struct endo_layout *layout, u16 endo_id)
-{
- /* Validate Endo Size */
- if (endo_is_large(endo_id)) {
- /* Large Endo type */
- layout->max_ribs = ENDO_BACK_RIBS_LARGE;
- } else if (endo_is_medium(endo_id)) {
- /* Medium Endo type */
- layout->max_ribs = ENDO_BACK_RIBS_MEDIUM;
- } else if (endo_is_mini(endo_id)) {
- /* Mini Endo type */
- layout->max_ribs = ENDO_BACK_RIBS_MINI;
- } else {
- dev_err(&hd->dev, "%s: Invalid endo type, id 0x%04x\n",
- __func__, endo_id);
- return -EINVAL;
- }
-
- if (!validate_back_ribs(hd, layout, endo_id))
- return -EINVAL;
-
- if (!validate_front_ribs(hd, layout,
- layout->max_ribs == ENDO_BACK_RIBS_MINI,
- endo_id))
- return -EINVAL;
-
- return 0;
-}
-
-/*
- * Look up which module contains the given interface.
- *
- * A module's ID is the same as its lowest-numbered interface ID. So the module
- * ID for a 1x1 module is always the same as its interface ID.
- *
- * For Endo Back:
- * The module ID for an interface on a 1x2 or 2x2 module (which use two
- * interface blocks) can be either the interface ID, or one less than the
- * interface ID if there is no rib "above" the interface.
- *
- * For Endo Front:
- * There are three rib locations in front and all of them might be unused, i.e.
- * a single module is used for all 4 interfaces. We need to check all ribs in
- * that case to find module ID.
- */
-u8 endo_get_module_id(struct gb_endo *endo, u8 interface_id)
-{
- struct endo_layout *layout = &endo->layout;
- unsigned int height = layout->max_ribs + 1;
- unsigned int iid = interface_id - 1;
- unsigned int mask, rib_mask;
-
- if (!interface_id)
- return 0;
-
- if (iid < height) { /* back left */
- mask = layout->left_ribs;
- } else if (iid < 2 * height) { /* back right */
- mask = layout->right_ribs;
- iid -= height;
- } else { /* front */
- mask = layout->front_ribs;
- iid -= 2 * height;
- }
-
- /*
- * Find the next rib *above* this interface to determine the lowest
- * interface ID in the module.
- */
- rib_mask = 1 << iid;
- while ((rib_mask >>= 1) != 0 && !(mask & rib_mask))
- --interface_id;
-
- return interface_id;
-}
-
-/*
- * Creates all possible modules for the Endo.
- *
- * We try to create modules for all possible interface IDs. If a module is
- * already created, we skip creating it again with the help of prev_module_id.
- */
-static int create_modules(struct gb_endo *endo)
-{
- struct gb_module *module;
- int prev_module_id = 0;
- int interface_id;
- int module_id;
- int max_id;
-
- max_id = max_endo_interface_id(&endo->layout);
-
- /* Find module corresponding to each interface */
- for (interface_id = 1; interface_id <= max_id; interface_id++) {
- module_id = endo_get_module_id(endo, interface_id);
-
- if (WARN_ON(!module_id))
- continue;
-
- /* Skip already created modules */
- if (module_id == prev_module_id)
- continue;
-
- prev_module_id = module_id;
-
- /* New module, create it */
- module = gb_module_create(&endo->dev, module_id);
- if (!module)
- return -EINVAL;
- }
-
- return 0;
-}
-
-static int gb_endo_register(struct gb_host_device *hd,
- struct gb_endo *endo)
-{
- int dev_id;
- int retval;
-
- dev_id = ida_simple_get(&greybus_endo_id_map, 0, 0, GFP_KERNEL);
- if (dev_id < 0)
- return dev_id;
-
- endo->dev_id = dev_id;
-
- endo->dev.parent = &hd->dev;
- endo->dev.bus = &greybus_bus_type;
- endo->dev.type = &greybus_endo_type;
- endo->dev.groups = endo_groups;
- endo->dev.dma_mask = hd->dev.dma_mask;
- device_initialize(&endo->dev);
- dev_set_name(&endo->dev, "endo%hu", endo->dev_id);
-
- // FIXME
- // Get the version and serial number from the SVC, right now we are
- // using "fake" numbers.
- strcpy(&endo->svc_info.serial_number[0], "042");
- strcpy(&endo->svc_info.version[0], "0.0");
-
- retval = device_add(&endo->dev);
- if (retval) {
- dev_err(&hd->dev, "failed to add endo device of id 0x%04x\n",
- endo->id);
- put_device(&endo->dev);
- }
-
- return retval;
-}
-
-struct gb_endo *gb_endo_create(struct gb_host_device *hd, u16 endo_id,
- u8 ap_intf_id)
-{
- struct gb_endo *endo;
- int retval;
-
- endo = kzalloc(sizeof(*endo), GFP_KERNEL);
- if (!endo)
- return ERR_PTR(-ENOMEM);
-
- /* First check if the value supplied is a valid endo id */
- if (gb_endo_validate_id(hd, &endo->layout, endo_id)) {
- retval = -EINVAL;
- goto free_endo;
- }
- if (ap_intf_id > max_endo_interface_id(&endo->layout)) {
- retval = -EINVAL;
- goto free_endo;
- }
-
- /* Register Endo device */
- retval = gb_endo_register(hd, endo);
- if (retval)
- goto free_endo;
-
- /* Create modules/interfaces */
- retval = create_modules(endo);
- if (retval) {
- gb_endo_remove(endo);
- return NULL;
- }
-
- return endo;
-
-free_endo:
- kfree(endo);
-
- return ERR_PTR(retval);
-}
-
-void gb_endo_remove(struct gb_endo *endo)
-{
- if (!endo)
- return;
-
- /* remove all modules for this endo */
- gb_module_remove_all(endo);
-
- device_unregister(&endo->dev);
-}
-
-int greybus_endo_setup(struct gb_host_device *hd, u16 endo_id,
- u8 ap_intf_id)
-{
- struct gb_endo *endo;
-
- endo = gb_endo_create(hd, endo_id, ap_intf_id);
- if (IS_ERR(endo))
- return PTR_ERR(endo);
- hd->endo = endo;
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(greybus_endo_setup);
-
-int __init gb_endo_init(void)
-{
- ida_init(&greybus_endo_id_map);
-
- return 0;
-}
-
-void gb_endo_exit(void)
-{
- ida_destroy(&greybus_endo_id_map);
-}
+++ /dev/null
-/*
- * Greybus module code
- *
- * Copyright 2014 Google Inc.
- * Copyright 2014 Linaro Ltd.
- *
- * Released under the GPLv2 only.
- */
-
-#include "greybus.h"
-
-
-/* module sysfs attributes */
-static ssize_t epm_show(struct device *dev, struct device_attribute *attr,
- char *buf)
-{
- // FIXME
- // Implement something here when we have a working control protocol
- return sprintf(buf, "1\n");
-}
-
-static ssize_t epm_store(struct device *dev, struct device_attribute *attr,
- const char *buf, size_t size)
-{
- // FIXME
- // Implement something here when we have a working control protocol
- return 0;
-}
-static DEVICE_ATTR_RW(epm);
-
-static ssize_t power_control_show(struct device *dev,
- struct device_attribute *addr, char *buf)
-{
- // FIXME
- // Implement something here when we have a working control protocol
- return sprintf(buf, "1\n");
-}
-
-static ssize_t power_control_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t size)
-{
- // FIXME
- // Implement something here when we have a working control protocol
- return 0;
-}
-static DEVICE_ATTR_RW(power_control);
-
-static ssize_t present_show(struct device *dev,
- struct device_attribute *addr, char *buf)
-{
- // FIXME
- // Implement something here when we have a working control protocol
- return sprintf(buf, "1\n");
-}
-
-static ssize_t present_store(struct device *dev, struct device_attribute *attr,
- const char *buf, size_t size)
-{
- // FIXME
- // Implement something here when we have a working control protocol
- return 0;
-}
-static DEVICE_ATTR_RW(present);
-
-static struct attribute *module_attrs[] = {
- &dev_attr_epm.attr,
- &dev_attr_power_control.attr,
- &dev_attr_present.attr,
- NULL,
-};
-ATTRIBUTE_GROUPS(module);
-
-static void gb_module_release(struct device *dev)
-{
- struct gb_module *module = to_gb_module(dev);
-
- kfree(module);
-}
-
-struct device_type greybus_module_type = {
- .name = "greybus_module",
- .release = gb_module_release,
-};
-
-struct module_find {
- struct gb_endo *endo;
- u8 module_id;
-};
-
-static int module_find(struct device *dev, void *data)
-{
- struct gb_module *module;
- struct module_find *find = data;
-
- if (!is_gb_module(dev))
- return 0;
-
- module = to_gb_module(dev);
- if ((module->module_id == find->module_id) &&
- (module->dev.parent == &find->endo->dev))
- return 1;
-
- return 0;
-}
-
-/*
- * Search the list of modules in the system. If one is found, return it, with
- * the reference count incremented.
- */
-struct gb_module *gb_module_find(struct gb_host_device *hd, u8 module_id)
-{
- struct device *dev;
- struct gb_module *module = NULL;
- struct module_find find;
-
- if (!module_id)
- return NULL;
-
- find.module_id = module_id;
- find.endo = hd->endo;
-
- dev = bus_find_device(&greybus_bus_type, NULL,
- &find, module_find);
- if (dev)
- module = to_gb_module(dev);
-
- return module;
-}
-
-struct gb_module *gb_module_create(struct device *parent, u8 module_id)
-{
- struct gb_module *module;
- int retval;
-
- module = kzalloc(sizeof(*module), GFP_KERNEL);
- if (!module)
- return NULL;
-
- module->module_id = module_id;
- module->dev.parent = parent;
- module->dev.bus = &greybus_bus_type;
- module->dev.type = &greybus_module_type;
- module->dev.groups = module_groups;
- module->dev.dma_mask = parent->dma_mask;
- device_initialize(&module->dev);
- dev_set_name(&module->dev, "%s:%hhu", dev_name(parent), module_id);
-
- retval = device_add(&module->dev);
- if (retval) {
- pr_err("failed to add module device for id 0x%02hhx\n",
- module_id);
- put_device(&module->dev);
- return NULL;
- }
-
- return module;
-}
-
-static int module_remove(struct device *dev, void *data)
-{
- struct gb_module *module;
- struct gb_endo *endo = data;
-
- if (!is_gb_module(dev))
- return 0;
-
- module = to_gb_module(dev);
- if (module->dev.parent == &endo->dev)
- device_unregister(&module->dev);
-
- return 0;
-}
-
-void gb_module_remove_all(struct gb_endo *endo)
-{
- bus_for_each_dev(&greybus_bus_type, NULL, endo, module_remove);
-}
projects / platform / kernel / linux-rpi.git / commitdiff