1 // SPDX-License-Identifier: GPL-2.0-only
5 * Copyright (C) IBM Corporation 2016
10 * - s/cfam/chip (cfam_id -> chip_id etc...)
13 #include <linux/crc4.h>
14 #include <linux/device.h>
15 #include <linux/fsi.h>
16 #include <linux/idr.h>
17 #include <linux/module.h>
19 #include <linux/of_address.h>
20 #include <linux/of_device.h>
21 #include <linux/slab.h>
22 #include <linux/bitops.h>
23 #include <linux/cdev.h>
25 #include <linux/uaccess.h>
27 #include "fsi-master.h"
28 #include "fsi-slave.h"
30 #define CREATE_TRACE_POINTS
31 #include <trace/events/fsi.h>
33 #define FSI_SLAVE_CONF_NEXT_MASK GENMASK(31, 31)
34 #define FSI_SLAVE_CONF_SLOTS_MASK GENMASK(23, 16)
35 #define FSI_SLAVE_CONF_SLOTS_SHIFT 16
36 #define FSI_SLAVE_CONF_VERSION_MASK GENMASK(15, 12)
37 #define FSI_SLAVE_CONF_VERSION_SHIFT 12
38 #define FSI_SLAVE_CONF_TYPE_MASK GENMASK(11, 4)
39 #define FSI_SLAVE_CONF_TYPE_SHIFT 4
40 #define FSI_SLAVE_CONF_CRC_SHIFT 4
41 #define FSI_SLAVE_CONF_CRC_MASK GENMASK(3, 0)
42 #define FSI_SLAVE_CONF_DATA_BITS 28
44 #define FSI_PEEK_BASE 0x410
46 static const int engine_page_size = 0x400;
48 #define FSI_SLAVE_BASE 0x800
51 * FSI slave engine control register offsets
53 #define FSI_SMODE 0x0 /* R/W: Mode register */
54 #define FSI_SISC 0x8 /* R/W: Interrupt condition */
55 #define FSI_SSTAT 0x14 /* R : Slave status */
56 #define FSI_SLBUS 0x30 /* W : LBUS Ownership */
57 #define FSI_LLMODE 0x100 /* R/W: Link layer mode register */
62 #define FSI_SMODE_WSC 0x80000000 /* Warm start done */
63 #define FSI_SMODE_ECRC 0x20000000 /* Hw CRC check */
64 #define FSI_SMODE_SID_SHIFT 24 /* ID shift */
65 #define FSI_SMODE_SID_MASK 3 /* ID Mask */
66 #define FSI_SMODE_ED_SHIFT 20 /* Echo delay shift */
67 #define FSI_SMODE_ED_MASK 0xf /* Echo delay mask */
68 #define FSI_SMODE_SD_SHIFT 16 /* Send delay shift */
69 #define FSI_SMODE_SD_MASK 0xf /* Send delay mask */
70 #define FSI_SMODE_LBCRR_SHIFT 8 /* Clk ratio shift */
71 #define FSI_SMODE_LBCRR_MASK 0xf /* Clk ratio mask */
76 #define FSI_SLBUS_FORCE 0x80000000 /* Force LBUS ownership */
81 #define FSI_LLMODE_ASYNC 0x1
83 #define FSI_SLAVE_SIZE_23b 0x800000
85 static DEFINE_IDA(master_ida);
87 static const int slave_retries = 2;
88 static int discard_errors;
90 static dev_t fsi_base_dev;
91 static DEFINE_IDA(fsi_minor_ida);
92 #define FSI_CHAR_MAX_DEVICES 0x1000
94 /* Legacy /dev numbering: 4 devices per chip, 16 chips */
95 #define FSI_CHAR_LEGACY_TOP 64
97 static int fsi_master_read(struct fsi_master *master, int link,
98 uint8_t slave_id, uint32_t addr, void *val, size_t size);
99 static int fsi_master_write(struct fsi_master *master, int link,
100 uint8_t slave_id, uint32_t addr, const void *val, size_t size);
101 static int fsi_master_break(struct fsi_master *master, int link);
104 * fsi_device_read() / fsi_device_write() / fsi_device_peek()
106 * FSI endpoint-device support
108 * Read / write / peek accessors for a client
111 * dev: Structure passed to FSI client device drivers on probe().
112 * addr: FSI address of given device. Client should pass in its base address
113 * plus desired offset to access its register space.
114 * val: For read/peek this is the value read at the specified address. For
115 * write this is value to write to the specified address.
116 * The data in val must be FSI bus endian (big endian).
117 * size: Size in bytes of the operation. Sizes supported are 1, 2 and 4 bytes.
118 * Addresses must be aligned on size boundaries or an error will result.
120 int fsi_device_read(struct fsi_device *dev, uint32_t addr, void *val,
123 if (addr > dev->size || size > dev->size || addr > dev->size - size)
126 return fsi_slave_read(dev->slave, dev->addr + addr, val, size);
128 EXPORT_SYMBOL_GPL(fsi_device_read);
130 int fsi_device_write(struct fsi_device *dev, uint32_t addr, const void *val,
133 if (addr > dev->size || size > dev->size || addr > dev->size - size)
136 return fsi_slave_write(dev->slave, dev->addr + addr, val, size);
138 EXPORT_SYMBOL_GPL(fsi_device_write);
140 int fsi_device_peek(struct fsi_device *dev, void *val)
142 uint32_t addr = FSI_PEEK_BASE + ((dev->unit - 2) * sizeof(uint32_t));
144 return fsi_slave_read(dev->slave, addr, val, sizeof(uint32_t));
147 static void fsi_device_release(struct device *_device)
149 struct fsi_device *device = to_fsi_dev(_device);
151 of_node_put(device->dev.of_node);
155 static struct fsi_device *fsi_create_device(struct fsi_slave *slave)
157 struct fsi_device *dev;
159 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
163 dev->dev.parent = &slave->dev;
164 dev->dev.bus = &fsi_bus_type;
165 dev->dev.release = fsi_device_release;
170 /* FSI slave support */
171 static int fsi_slave_calc_addr(struct fsi_slave *slave, uint32_t *addrp,
174 uint32_t addr = *addrp;
177 if (addr > slave->size)
180 /* For 23 bit addressing, we encode the extra two bits in the slave
181 * id (and the slave's actual ID needs to be 0).
183 if (addr > 0x1fffff) {
186 id = (addr >> 21) & 0x3;
195 static int fsi_slave_report_and_clear_errors(struct fsi_slave *slave)
197 struct fsi_master *master = slave->master;
205 rc = fsi_master_read(master, link, id, FSI_SLAVE_BASE + FSI_SISC,
210 rc = fsi_master_read(master, link, id, FSI_SLAVE_BASE + FSI_SSTAT,
211 &stat, sizeof(stat));
215 dev_dbg(&slave->dev, "status: 0x%08x, sisc: 0x%08x\n",
216 be32_to_cpu(stat), be32_to_cpu(irq));
218 /* clear interrupts */
219 return fsi_master_write(master, link, id, FSI_SLAVE_BASE + FSI_SISC,
223 /* Encode slave local bus echo delay */
224 static inline uint32_t fsi_smode_echodly(int x)
226 return (x & FSI_SMODE_ED_MASK) << FSI_SMODE_ED_SHIFT;
229 /* Encode slave local bus send delay */
230 static inline uint32_t fsi_smode_senddly(int x)
232 return (x & FSI_SMODE_SD_MASK) << FSI_SMODE_SD_SHIFT;
235 /* Encode slave local bus clock rate ratio */
236 static inline uint32_t fsi_smode_lbcrr(int x)
238 return (x & FSI_SMODE_LBCRR_MASK) << FSI_SMODE_LBCRR_SHIFT;
241 /* Encode slave ID */
242 static inline uint32_t fsi_smode_sid(int x)
244 return (x & FSI_SMODE_SID_MASK) << FSI_SMODE_SID_SHIFT;
247 static uint32_t fsi_slave_smode(int id, u8 t_senddly, u8 t_echodly)
249 return FSI_SMODE_WSC | FSI_SMODE_ECRC
251 | fsi_smode_echodly(t_echodly - 1) | fsi_smode_senddly(t_senddly - 1)
252 | fsi_smode_lbcrr(0x8);
255 static int fsi_slave_set_smode(struct fsi_slave *slave)
260 /* set our smode register with the slave ID field to 0; this enables
261 * extended slave addressing
263 smode = fsi_slave_smode(slave->id, slave->t_send_delay, slave->t_echo_delay);
264 data = cpu_to_be32(smode);
266 return fsi_master_write(slave->master, slave->link, slave->id,
267 FSI_SLAVE_BASE + FSI_SMODE,
268 &data, sizeof(data));
271 static int fsi_slave_handle_error(struct fsi_slave *slave, bool write,
272 uint32_t addr, size_t size)
274 struct fsi_master *master = slave->master;
277 uint8_t id, send_delay, echo_delay;
285 dev_dbg(&slave->dev, "handling error on %s to 0x%08x[%zd]",
286 write ? "write" : "read", addr, size);
288 /* try a simple clear of error conditions, which may fail if we've lost
289 * communication with the slave
291 rc = fsi_slave_report_and_clear_errors(slave);
295 /* send a TERM and retry */
297 rc = master->term(master, link, id);
299 rc = fsi_master_read(master, link, id, 0,
302 rc = fsi_slave_report_and_clear_errors(slave);
308 send_delay = slave->t_send_delay;
309 echo_delay = slave->t_echo_delay;
311 /* getting serious, reset the slave via BREAK */
312 rc = fsi_master_break(master, link);
316 slave->t_send_delay = send_delay;
317 slave->t_echo_delay = echo_delay;
319 rc = fsi_slave_set_smode(slave);
323 if (master->link_config)
324 master->link_config(master, link,
326 slave->t_echo_delay);
328 return fsi_slave_report_and_clear_errors(slave);
331 int fsi_slave_read(struct fsi_slave *slave, uint32_t addr,
332 void *val, size_t size)
334 uint8_t id = slave->id;
337 rc = fsi_slave_calc_addr(slave, &addr, &id);
341 for (i = 0; i < slave_retries; i++) {
342 rc = fsi_master_read(slave->master, slave->link,
343 id, addr, val, size);
347 err_rc = fsi_slave_handle_error(slave, false, addr, size);
354 EXPORT_SYMBOL_GPL(fsi_slave_read);
356 int fsi_slave_write(struct fsi_slave *slave, uint32_t addr,
357 const void *val, size_t size)
359 uint8_t id = slave->id;
362 rc = fsi_slave_calc_addr(slave, &addr, &id);
366 for (i = 0; i < slave_retries; i++) {
367 rc = fsi_master_write(slave->master, slave->link,
368 id, addr, val, size);
372 err_rc = fsi_slave_handle_error(slave, true, addr, size);
379 EXPORT_SYMBOL_GPL(fsi_slave_write);
381 int fsi_slave_claim_range(struct fsi_slave *slave,
382 uint32_t addr, uint32_t size)
384 if (addr + size < addr)
387 if (addr + size > slave->size)
390 /* todo: check for overlapping claims */
393 EXPORT_SYMBOL_GPL(fsi_slave_claim_range);
395 void fsi_slave_release_range(struct fsi_slave *slave,
396 uint32_t addr, uint32_t size)
399 EXPORT_SYMBOL_GPL(fsi_slave_release_range);
401 static bool fsi_device_node_matches(struct device *dev, struct device_node *np,
402 uint32_t addr, uint32_t size)
406 if (of_property_read_reg(np, 0, &paddr, &psize))
414 "node %pOF matches probed address, but not size (got 0x%llx, expected 0x%x)",
421 /* Find a matching node for the slave engine at @address, using @size bytes
422 * of space. Returns NULL if not found, or a matching node with refcount
423 * already incremented.
425 static struct device_node *fsi_device_find_of_node(struct fsi_device *dev)
427 struct device_node *parent, *np;
429 parent = dev_of_node(&dev->slave->dev);
433 for_each_child_of_node(parent, np) {
434 if (fsi_device_node_matches(&dev->dev, np,
435 dev->addr, dev->size))
442 static int fsi_slave_scan(struct fsi_slave *slave)
444 uint32_t engine_addr;
450 * We keep the peek mode and slave engines for the core; so start
451 * at the third slot in the configuration table. We also need to
452 * skip the chip ID entry at the start of the address space.
454 engine_addr = engine_page_size * 3;
455 for (i = 2; i < engine_page_size / sizeof(uint32_t); i++) {
456 uint8_t slots, version, type, crc;
457 struct fsi_device *dev;
461 rc = fsi_slave_read(slave, (i + 1) * sizeof(data),
462 &data, sizeof(data));
464 dev_warn(&slave->dev,
465 "error reading slave registers\n");
468 conf = be32_to_cpu(data);
470 crc = crc4(0, conf, 32);
472 dev_warn(&slave->dev,
473 "crc error in slave register at 0x%04x\n",
478 slots = (conf & FSI_SLAVE_CONF_SLOTS_MASK)
479 >> FSI_SLAVE_CONF_SLOTS_SHIFT;
480 version = (conf & FSI_SLAVE_CONF_VERSION_MASK)
481 >> FSI_SLAVE_CONF_VERSION_SHIFT;
482 type = (conf & FSI_SLAVE_CONF_TYPE_MASK)
483 >> FSI_SLAVE_CONF_TYPE_SHIFT;
486 * Unused address areas are marked by a zero type value; this
487 * skips the defined address areas
489 if (type != 0 && slots != 0) {
492 dev = fsi_create_device(slave);
497 dev->engine_type = type;
498 dev->version = version;
500 dev->addr = engine_addr;
501 dev->size = slots * engine_page_size;
503 trace_fsi_dev_init(dev);
506 "engine[%i]: type %x, version %x, addr %x size %x\n",
507 dev->unit, dev->engine_type, version,
508 dev->addr, dev->size);
510 dev_set_name(&dev->dev, "%02x:%02x:%02x:%02x",
511 slave->master->idx, slave->link,
513 dev->dev.of_node = fsi_device_find_of_node(dev);
515 rc = device_register(&dev->dev);
517 dev_warn(&slave->dev, "add failed: %d\n", rc);
518 put_device(&dev->dev);
522 engine_addr += slots * engine_page_size;
524 if (!(conf & FSI_SLAVE_CONF_NEXT_MASK))
531 static unsigned long aligned_access_size(size_t offset, size_t count)
533 unsigned long offset_unit, count_unit;
537 * 1. Access size must be less than or equal to the maximum access
538 * width or the highest power-of-two factor of offset
539 * 2. Access size must be less than or equal to the amount specified by
542 * The access width is optimal if we can calculate 1 to be strictly
543 * equal while still satisfying 2.
546 /* Find 1 by the bottom bit of offset (with a 4 byte access cap) */
547 offset_unit = BIT(__builtin_ctzl(offset | 4));
549 /* Find 2 by the top bit of count */
550 count_unit = BIT(8 * sizeof(unsigned long) - 1 - __builtin_clzl(count));
552 /* Constrain the maximum access width to the minimum of both criteria */
553 return BIT(__builtin_ctzl(offset_unit | count_unit));
556 static ssize_t fsi_slave_sysfs_raw_read(struct file *file,
557 struct kobject *kobj, struct bin_attribute *attr, char *buf,
558 loff_t off, size_t count)
560 struct fsi_slave *slave = to_fsi_slave(kobj_to_dev(kobj));
561 size_t total_len, read_len;
567 if (off > 0xffffffff || count > 0xffffffff || off + count > 0xffffffff)
570 for (total_len = 0; total_len < count; total_len += read_len) {
571 read_len = aligned_access_size(off, count - total_len);
573 rc = fsi_slave_read(slave, off, buf + total_len, read_len);
583 static ssize_t fsi_slave_sysfs_raw_write(struct file *file,
584 struct kobject *kobj, struct bin_attribute *attr,
585 char *buf, loff_t off, size_t count)
587 struct fsi_slave *slave = to_fsi_slave(kobj_to_dev(kobj));
588 size_t total_len, write_len;
594 if (off > 0xffffffff || count > 0xffffffff || off + count > 0xffffffff)
597 for (total_len = 0; total_len < count; total_len += write_len) {
598 write_len = aligned_access_size(off, count - total_len);
600 rc = fsi_slave_write(slave, off, buf + total_len, write_len);
610 static const struct bin_attribute fsi_slave_raw_attr = {
616 .read = fsi_slave_sysfs_raw_read,
617 .write = fsi_slave_sysfs_raw_write,
620 static void fsi_slave_release(struct device *dev)
622 struct fsi_slave *slave = to_fsi_slave(dev);
624 fsi_free_minor(slave->dev.devt);
625 of_node_put(dev->of_node);
629 static bool fsi_slave_node_matches(struct device_node *np,
630 int link, uint8_t id)
634 if (of_property_read_reg(np, 0, &addr, NULL))
637 return addr == (((u64)link << 32) | id);
640 /* Find a matching node for the slave at (link, id). Returns NULL if none
641 * found, or a matching node with refcount already incremented.
643 static struct device_node *fsi_slave_find_of_node(struct fsi_master *master,
644 int link, uint8_t id)
646 struct device_node *parent, *np;
648 parent = dev_of_node(&master->dev);
652 for_each_child_of_node(parent, np) {
653 if (fsi_slave_node_matches(np, link, id))
660 static ssize_t cfam_read(struct file *filep, char __user *buf, size_t count,
663 struct fsi_slave *slave = filep->private_data;
664 size_t total_len, read_len;
665 loff_t off = *offset;
671 if (off > 0xffffffff || count > 0xffffffff || off + count > 0xffffffff)
674 for (total_len = 0; total_len < count; total_len += read_len) {
677 read_len = min_t(size_t, count, 4);
678 read_len -= off & 0x3;
680 rc = fsi_slave_read(slave, off, &data, read_len);
683 rc = copy_to_user(buf + total_len, &data, read_len);
696 static ssize_t cfam_write(struct file *filep, const char __user *buf,
697 size_t count, loff_t *offset)
699 struct fsi_slave *slave = filep->private_data;
700 size_t total_len, write_len;
701 loff_t off = *offset;
708 if (off > 0xffffffff || count > 0xffffffff || off + count > 0xffffffff)
711 for (total_len = 0; total_len < count; total_len += write_len) {
714 write_len = min_t(size_t, count, 4);
715 write_len -= off & 0x3;
717 rc = copy_from_user(&data, buf + total_len, write_len);
722 rc = fsi_slave_write(slave, off, &data, write_len);
733 static loff_t cfam_llseek(struct file *file, loff_t offset, int whence)
739 file->f_pos = offset;
748 static int cfam_open(struct inode *inode, struct file *file)
750 struct fsi_slave *slave = container_of(inode->i_cdev, struct fsi_slave, cdev);
752 file->private_data = slave;
757 static const struct file_operations cfam_fops = {
758 .owner = THIS_MODULE,
760 .llseek = cfam_llseek,
765 static ssize_t send_term_store(struct device *dev,
766 struct device_attribute *attr,
767 const char *buf, size_t count)
769 struct fsi_slave *slave = to_fsi_slave(dev);
770 struct fsi_master *master = slave->master;
775 master->term(master, slave->link, slave->id);
779 static DEVICE_ATTR_WO(send_term);
781 static ssize_t slave_send_echo_show(struct device *dev,
782 struct device_attribute *attr,
785 struct fsi_slave *slave = to_fsi_slave(dev);
787 return sprintf(buf, "%u\n", slave->t_send_delay);
790 static ssize_t slave_send_echo_store(struct device *dev,
791 struct device_attribute *attr, const char *buf, size_t count)
793 struct fsi_slave *slave = to_fsi_slave(dev);
794 struct fsi_master *master = slave->master;
798 if (kstrtoul(buf, 0, &val) < 0)
801 if (val < 1 || val > 16)
804 if (!master->link_config)
807 /* Current HW mandates that send and echo delay are identical */
808 slave->t_send_delay = val;
809 slave->t_echo_delay = val;
811 rc = fsi_slave_set_smode(slave);
814 if (master->link_config)
815 master->link_config(master, slave->link,
817 slave->t_echo_delay);
822 static DEVICE_ATTR(send_echo_delays, 0600,
823 slave_send_echo_show, slave_send_echo_store);
825 static ssize_t chip_id_show(struct device *dev,
826 struct device_attribute *attr,
829 struct fsi_slave *slave = to_fsi_slave(dev);
831 return sprintf(buf, "%d\n", slave->chip_id);
834 static DEVICE_ATTR_RO(chip_id);
836 static ssize_t cfam_id_show(struct device *dev,
837 struct device_attribute *attr,
840 struct fsi_slave *slave = to_fsi_slave(dev);
842 return sprintf(buf, "0x%x\n", slave->cfam_id);
845 static DEVICE_ATTR_RO(cfam_id);
847 static struct attribute *cfam_attr[] = {
848 &dev_attr_send_echo_delays.attr,
849 &dev_attr_chip_id.attr,
850 &dev_attr_cfam_id.attr,
851 &dev_attr_send_term.attr,
855 static const struct attribute_group cfam_attr_group = {
859 static const struct attribute_group *cfam_attr_groups[] = {
864 static char *cfam_devnode(const struct device *dev, umode_t *mode,
865 kuid_t *uid, kgid_t *gid)
867 const struct fsi_slave *slave = to_fsi_slave(dev);
869 #ifdef CONFIG_FSI_NEW_DEV_NODE
870 return kasprintf(GFP_KERNEL, "fsi/cfam%d", slave->cdev_idx);
872 return kasprintf(GFP_KERNEL, "cfam%d", slave->cdev_idx);
876 static const struct device_type cfam_type = {
878 .devnode = cfam_devnode,
879 .groups = cfam_attr_groups
882 static char *fsi_cdev_devnode(const struct device *dev, umode_t *mode,
883 kuid_t *uid, kgid_t *gid)
885 #ifdef CONFIG_FSI_NEW_DEV_NODE
886 return kasprintf(GFP_KERNEL, "fsi/%s", dev_name(dev));
888 return kasprintf(GFP_KERNEL, "%s", dev_name(dev));
892 const struct device_type fsi_cdev_type = {
894 .devnode = fsi_cdev_devnode,
896 EXPORT_SYMBOL_GPL(fsi_cdev_type);
898 /* Backward compatible /dev/ numbering in "old style" mode */
899 static int fsi_adjust_index(int index)
901 #ifdef CONFIG_FSI_NEW_DEV_NODE
908 static int __fsi_get_new_minor(struct fsi_slave *slave, enum fsi_dev_type type,
909 dev_t *out_dev, int *out_index)
911 int cid = slave->chip_id;
914 /* Check if we qualify for legacy numbering */
915 if (cid >= 0 && cid < 16 && type < 4) {
917 * Try reserving the legacy number, which has 0 - 0x3f reserved
918 * in the ida range. cid goes up to 0xf and type contains two
919 * bits, so construct the id with the below two bit shift.
921 id = (cid << 2) | type;
922 id = ida_alloc_range(&fsi_minor_ida, id, id, GFP_KERNEL);
924 *out_index = fsi_adjust_index(cid);
925 *out_dev = fsi_base_dev + id;
931 /* Fallback to non-legacy allocation */
933 id = ida_alloc_range(&fsi_minor_ida, FSI_CHAR_LEGACY_TOP,
934 FSI_CHAR_MAX_DEVICES - 1, GFP_KERNEL);
937 *out_index = fsi_adjust_index(id);
938 *out_dev = fsi_base_dev + id;
942 static const char *const fsi_dev_type_names[] = {
949 int fsi_get_new_minor(struct fsi_device *fdev, enum fsi_dev_type type,
950 dev_t *out_dev, int *out_index)
952 if (fdev->dev.of_node) {
953 int aid = of_alias_get_id(fdev->dev.of_node, fsi_dev_type_names[type]);
956 /* Use the same scheme as the legacy numbers. */
957 int id = (aid << 2) | type;
959 id = ida_alloc_range(&fsi_minor_ida, id, id, GFP_KERNEL);
962 *out_dev = fsi_base_dev + id;
971 return __fsi_get_new_minor(fdev->slave, type, out_dev, out_index);
973 EXPORT_SYMBOL_GPL(fsi_get_new_minor);
975 void fsi_free_minor(dev_t dev)
977 ida_free(&fsi_minor_ida, MINOR(dev));
979 EXPORT_SYMBOL_GPL(fsi_free_minor);
981 static int fsi_slave_init(struct fsi_master *master, int link, uint8_t id)
984 struct fsi_slave *slave;
986 __be32 data, llmode, slbus;
989 /* Currently, we only support single slaves on a link, and use the
990 * full 23-bit address range
995 rc = fsi_master_read(master, link, id, 0, &data, sizeof(data));
997 dev_dbg(&master->dev, "can't read slave %02x:%02x %d\n",
1001 cfam_id = be32_to_cpu(data);
1003 crc = crc4(0, cfam_id, 32);
1005 trace_fsi_slave_invalid_cfam(master, link, cfam_id);
1006 dev_warn(&master->dev, "slave %02x:%02x invalid cfam id CRC!\n",
1011 dev_dbg(&master->dev, "fsi: found chip %08x at %02x:%02x:%02x\n",
1012 cfam_id, master->idx, link, id);
1014 /* If we're behind a master that doesn't provide a self-running bus
1015 * clock, put the slave into async mode
1017 if (master->flags & FSI_MASTER_FLAG_SWCLOCK) {
1018 llmode = cpu_to_be32(FSI_LLMODE_ASYNC);
1019 rc = fsi_master_write(master, link, id,
1020 FSI_SLAVE_BASE + FSI_LLMODE,
1021 &llmode, sizeof(llmode));
1023 dev_warn(&master->dev,
1024 "can't set llmode on slave:%02x:%02x %d\n",
1028 /* We can communicate with a slave; create the slave device and
1031 slave = kzalloc(sizeof(*slave), GFP_KERNEL);
1035 dev_set_name(&slave->dev, "slave@%02x:%02x", link, id);
1036 slave->dev.type = &cfam_type;
1037 slave->dev.parent = &master->dev;
1038 slave->dev.of_node = fsi_slave_find_of_node(master, link, id);
1039 slave->dev.release = fsi_slave_release;
1040 device_initialize(&slave->dev);
1041 slave->cfam_id = cfam_id;
1042 slave->master = master;
1045 slave->size = FSI_SLAVE_SIZE_23b;
1046 slave->t_send_delay = 16;
1047 slave->t_echo_delay = 16;
1049 /* Get chip ID if any */
1050 slave->chip_id = -1;
1051 if (slave->dev.of_node) {
1053 if (!of_property_read_u32(slave->dev.of_node, "chip-id", &prop))
1054 slave->chip_id = prop;
1058 slbus = cpu_to_be32(FSI_SLBUS_FORCE);
1059 rc = fsi_master_write(master, link, id, FSI_SLAVE_BASE + FSI_SLBUS,
1060 &slbus, sizeof(slbus));
1062 dev_warn(&master->dev,
1063 "can't set slbus on slave:%02x:%02x %d\n", link, id,
1066 rc = fsi_slave_set_smode(slave);
1068 dev_warn(&master->dev,
1069 "can't set smode on slave:%02x:%02x %d\n",
1074 /* Allocate a minor in the FSI space */
1075 rc = __fsi_get_new_minor(slave, fsi_dev_cfam, &slave->dev.devt,
1080 trace_fsi_slave_init(slave);
1082 /* Create chardev for userspace access */
1083 cdev_init(&slave->cdev, &cfam_fops);
1084 rc = cdev_device_add(&slave->cdev, &slave->dev);
1086 dev_err(&slave->dev, "Error %d creating slave device\n", rc);
1090 /* Now that we have the cdev registered with the core, any fatal
1091 * failures beyond this point will need to clean up through
1092 * cdev_device_del(). Fortunately though, nothing past here is fatal.
1095 if (master->link_config)
1096 master->link_config(master, link,
1097 slave->t_send_delay,
1098 slave->t_echo_delay);
1100 /* Legacy raw file -> to be removed */
1101 rc = device_create_bin_file(&slave->dev, &fsi_slave_raw_attr);
1103 dev_warn(&slave->dev, "failed to create raw attr: %d\n", rc);
1106 rc = fsi_slave_scan(slave);
1108 dev_dbg(&master->dev, "failed during slave scan with: %d\n",
1114 fsi_free_minor(slave->dev.devt);
1116 of_node_put(slave->dev.of_node);
1121 /* FSI master support */
1122 static int fsi_check_access(uint32_t addr, size_t size)
1127 } else if (size == 2) {
1130 } else if (size != 1)
1136 static int fsi_master_read(struct fsi_master *master, int link,
1137 uint8_t slave_id, uint32_t addr, void *val, size_t size)
1141 trace_fsi_master_read(master, link, slave_id, addr, size);
1143 rc = fsi_check_access(addr, size);
1145 rc = master->read(master, link, slave_id, addr, val, size);
1147 trace_fsi_master_rw_result(master, link, slave_id, addr, size,
1153 static int fsi_master_write(struct fsi_master *master, int link,
1154 uint8_t slave_id, uint32_t addr, const void *val, size_t size)
1158 trace_fsi_master_write(master, link, slave_id, addr, size, val);
1160 rc = fsi_check_access(addr, size);
1162 rc = master->write(master, link, slave_id, addr, val, size);
1164 trace_fsi_master_rw_result(master, link, slave_id, addr, size,
1170 static int fsi_master_link_disable(struct fsi_master *master, int link)
1172 if (master->link_enable)
1173 return master->link_enable(master, link, false);
1178 static int fsi_master_link_enable(struct fsi_master *master, int link)
1180 if (master->link_enable)
1181 return master->link_enable(master, link, true);
1187 * Issue a break command on this link
1189 static int fsi_master_break(struct fsi_master *master, int link)
1193 trace_fsi_master_break(master, link);
1195 if (master->send_break)
1196 rc = master->send_break(master, link);
1197 if (master->link_config)
1198 master->link_config(master, link, 16, 16);
1203 static int fsi_master_scan(struct fsi_master *master)
1207 trace_fsi_master_scan(master, true);
1208 for (link = 0; link < master->n_links; link++) {
1209 rc = fsi_master_link_enable(master, link);
1211 dev_dbg(&master->dev,
1212 "enable link %d failed: %d\n", link, rc);
1215 rc = fsi_master_break(master, link);
1217 fsi_master_link_disable(master, link);
1218 dev_dbg(&master->dev,
1219 "break to link %d failed: %d\n", link, rc);
1223 rc = fsi_slave_init(master, link, 0);
1225 fsi_master_link_disable(master, link);
1231 static int fsi_slave_remove_device(struct device *dev, void *arg)
1233 device_unregister(dev);
1237 static int fsi_master_remove_slave(struct device *dev, void *arg)
1239 struct fsi_slave *slave = to_fsi_slave(dev);
1241 device_for_each_child(dev, NULL, fsi_slave_remove_device);
1242 cdev_device_del(&slave->cdev, &slave->dev);
1247 static void fsi_master_unscan(struct fsi_master *master)
1249 trace_fsi_master_scan(master, false);
1250 device_for_each_child(&master->dev, NULL, fsi_master_remove_slave);
1253 int fsi_master_rescan(struct fsi_master *master)
1257 mutex_lock(&master->scan_lock);
1258 fsi_master_unscan(master);
1259 rc = fsi_master_scan(master);
1260 mutex_unlock(&master->scan_lock);
1264 EXPORT_SYMBOL_GPL(fsi_master_rescan);
1266 static ssize_t master_rescan_store(struct device *dev,
1267 struct device_attribute *attr, const char *buf, size_t count)
1269 struct fsi_master *master = to_fsi_master(dev);
1272 rc = fsi_master_rescan(master);
1279 static DEVICE_ATTR(rescan, 0200, NULL, master_rescan_store);
1281 static ssize_t master_break_store(struct device *dev,
1282 struct device_attribute *attr, const char *buf, size_t count)
1284 struct fsi_master *master = to_fsi_master(dev);
1286 fsi_master_break(master, 0);
1291 static DEVICE_ATTR(break, 0200, NULL, master_break_store);
1293 static struct attribute *master_attrs[] = {
1294 &dev_attr_break.attr,
1295 &dev_attr_rescan.attr,
1299 ATTRIBUTE_GROUPS(master);
1301 static struct class fsi_master_class = {
1302 .name = "fsi-master",
1303 .dev_groups = master_groups,
1306 int fsi_master_register(struct fsi_master *master)
1309 struct device_node *np;
1311 mutex_init(&master->scan_lock);
1313 /* Alloc the requested index if it's non-zero */
1315 master->idx = ida_alloc_range(&master_ida, master->idx,
1316 master->idx, GFP_KERNEL);
1318 master->idx = ida_alloc(&master_ida, GFP_KERNEL);
1321 if (master->idx < 0)
1324 if (!dev_name(&master->dev))
1325 dev_set_name(&master->dev, "fsi%d", master->idx);
1327 master->dev.class = &fsi_master_class;
1329 mutex_lock(&master->scan_lock);
1330 rc = device_register(&master->dev);
1332 ida_free(&master_ida, master->idx);
1336 np = dev_of_node(&master->dev);
1337 if (!of_property_read_bool(np, "no-scan-on-init")) {
1338 fsi_master_scan(master);
1341 mutex_unlock(&master->scan_lock);
1344 EXPORT_SYMBOL_GPL(fsi_master_register);
1346 void fsi_master_unregister(struct fsi_master *master)
1348 int idx = master->idx;
1350 trace_fsi_master_unregister(master);
1352 mutex_lock(&master->scan_lock);
1353 fsi_master_unscan(master);
1354 master->n_links = 0;
1355 mutex_unlock(&master->scan_lock);
1357 device_unregister(&master->dev);
1358 ida_free(&master_ida, idx);
1360 EXPORT_SYMBOL_GPL(fsi_master_unregister);
1362 /* FSI core & Linux bus type definitions */
1364 static int fsi_bus_match(struct device *dev, const struct device_driver *drv)
1366 struct fsi_device *fsi_dev = to_fsi_dev(dev);
1367 const struct fsi_driver *fsi_drv = to_fsi_drv(drv);
1368 const struct fsi_device_id *id;
1370 if (!fsi_drv->id_table)
1373 for (id = fsi_drv->id_table; id->engine_type; id++) {
1374 if (id->engine_type != fsi_dev->engine_type)
1376 if (id->version == FSI_VERSION_ANY ||
1377 id->version == fsi_dev->version) {
1378 if (drv->of_match_table) {
1379 if (of_driver_match_device(dev, drv))
1390 int fsi_driver_register(struct fsi_driver *fsi_drv)
1394 if (!fsi_drv->id_table)
1397 return driver_register(&fsi_drv->drv);
1399 EXPORT_SYMBOL_GPL(fsi_driver_register);
1401 void fsi_driver_unregister(struct fsi_driver *fsi_drv)
1403 driver_unregister(&fsi_drv->drv);
1405 EXPORT_SYMBOL_GPL(fsi_driver_unregister);
1407 struct bus_type fsi_bus_type = {
1409 .match = fsi_bus_match,
1411 EXPORT_SYMBOL_GPL(fsi_bus_type);
1413 static int __init fsi_init(void)
1417 rc = alloc_chrdev_region(&fsi_base_dev, 0, FSI_CHAR_MAX_DEVICES, "fsi");
1420 rc = bus_register(&fsi_bus_type);
1424 rc = class_register(&fsi_master_class);
1431 bus_unregister(&fsi_bus_type);
1433 unregister_chrdev_region(fsi_base_dev, FSI_CHAR_MAX_DEVICES);
1436 postcore_initcall(fsi_init);
1438 static void fsi_exit(void)
1440 class_unregister(&fsi_master_class);
1441 bus_unregister(&fsi_bus_type);
1442 unregister_chrdev_region(fsi_base_dev, FSI_CHAR_MAX_DEVICES);
1443 ida_destroy(&fsi_minor_ida);
1445 module_exit(fsi_exit);
1446 module_param(discard_errors, int, 0664);
1447 MODULE_DESCRIPTION("FSI core driver");
1448 MODULE_LICENSE("GPL");
1449 MODULE_PARM_DESC(discard_errors, "Don't invoke error handling on bus accesses");