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/slab.h>
20 #include <linux/bitops.h>
21 #include <linux/cdev.h>
23 #include <linux/uaccess.h>
25 #include "fsi-master.h"
27 #define CREATE_TRACE_POINTS
28 #include <trace/events/fsi.h>
30 #define FSI_SLAVE_CONF_NEXT_MASK GENMASK(31, 31)
31 #define FSI_SLAVE_CONF_SLOTS_MASK GENMASK(23, 16)
32 #define FSI_SLAVE_CONF_SLOTS_SHIFT 16
33 #define FSI_SLAVE_CONF_VERSION_MASK GENMASK(15, 12)
34 #define FSI_SLAVE_CONF_VERSION_SHIFT 12
35 #define FSI_SLAVE_CONF_TYPE_MASK GENMASK(11, 4)
36 #define FSI_SLAVE_CONF_TYPE_SHIFT 4
37 #define FSI_SLAVE_CONF_CRC_SHIFT 4
38 #define FSI_SLAVE_CONF_CRC_MASK GENMASK(3, 0)
39 #define FSI_SLAVE_CONF_DATA_BITS 28
41 #define FSI_PEEK_BASE 0x410
43 static const int engine_page_size = 0x400;
45 #define FSI_SLAVE_BASE 0x800
48 * FSI slave engine control register offsets
50 #define FSI_SMODE 0x0 /* R/W: Mode register */
51 #define FSI_SISC 0x8 /* R/W: Interrupt condition */
52 #define FSI_SSTAT 0x14 /* R : Slave status */
53 #define FSI_LLMODE 0x100 /* R/W: Link layer mode register */
58 #define FSI_SMODE_WSC 0x80000000 /* Warm start done */
59 #define FSI_SMODE_ECRC 0x20000000 /* Hw CRC check */
60 #define FSI_SMODE_SID_SHIFT 24 /* ID shift */
61 #define FSI_SMODE_SID_MASK 3 /* ID Mask */
62 #define FSI_SMODE_ED_SHIFT 20 /* Echo delay shift */
63 #define FSI_SMODE_ED_MASK 0xf /* Echo delay mask */
64 #define FSI_SMODE_SD_SHIFT 16 /* Send delay shift */
65 #define FSI_SMODE_SD_MASK 0xf /* Send delay mask */
66 #define FSI_SMODE_LBCRR_SHIFT 8 /* Clk ratio shift */
67 #define FSI_SMODE_LBCRR_MASK 0xf /* Clk ratio mask */
72 #define FSI_LLMODE_ASYNC 0x1
74 #define FSI_SLAVE_SIZE_23b 0x800000
76 static DEFINE_IDA(master_ida);
80 struct fsi_master *master;
83 int id; /* FSI address */
84 int link; /* FSI link# */
87 uint32_t size; /* size of slave address space */
92 #define to_fsi_master(d) container_of(d, struct fsi_master, dev)
93 #define to_fsi_slave(d) container_of(d, struct fsi_slave, dev)
95 static const int slave_retries = 2;
96 static int discard_errors;
98 static dev_t fsi_base_dev;
99 static DEFINE_IDA(fsi_minor_ida);
100 #define FSI_CHAR_MAX_DEVICES 0x1000
102 /* Legacy /dev numbering: 4 devices per chip, 16 chips */
103 #define FSI_CHAR_LEGACY_TOP 64
105 static int fsi_master_read(struct fsi_master *master, int link,
106 uint8_t slave_id, uint32_t addr, void *val, size_t size);
107 static int fsi_master_write(struct fsi_master *master, int link,
108 uint8_t slave_id, uint32_t addr, const void *val, size_t size);
109 static int fsi_master_break(struct fsi_master *master, int link);
112 * fsi_device_read() / fsi_device_write() / fsi_device_peek()
114 * FSI endpoint-device support
116 * Read / write / peek accessors for a client
119 * dev: Structure passed to FSI client device drivers on probe().
120 * addr: FSI address of given device. Client should pass in its base address
121 * plus desired offset to access its register space.
122 * val: For read/peek this is the value read at the specified address. For
123 * write this is value to write to the specified address.
124 * The data in val must be FSI bus endian (big endian).
125 * size: Size in bytes of the operation. Sizes supported are 1, 2 and 4 bytes.
126 * Addresses must be aligned on size boundaries or an error will result.
128 int fsi_device_read(struct fsi_device *dev, uint32_t addr, void *val,
131 if (addr > dev->size || size > dev->size || addr > dev->size - size)
134 return fsi_slave_read(dev->slave, dev->addr + addr, val, size);
136 EXPORT_SYMBOL_GPL(fsi_device_read);
138 int fsi_device_write(struct fsi_device *dev, uint32_t addr, const void *val,
141 if (addr > dev->size || size > dev->size || addr > dev->size - size)
144 return fsi_slave_write(dev->slave, dev->addr + addr, val, size);
146 EXPORT_SYMBOL_GPL(fsi_device_write);
148 int fsi_device_peek(struct fsi_device *dev, void *val)
150 uint32_t addr = FSI_PEEK_BASE + ((dev->unit - 2) * sizeof(uint32_t));
152 return fsi_slave_read(dev->slave, addr, val, sizeof(uint32_t));
155 static void fsi_device_release(struct device *_device)
157 struct fsi_device *device = to_fsi_dev(_device);
159 of_node_put(device->dev.of_node);
163 static struct fsi_device *fsi_create_device(struct fsi_slave *slave)
165 struct fsi_device *dev;
167 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
171 dev->dev.parent = &slave->dev;
172 dev->dev.bus = &fsi_bus_type;
173 dev->dev.release = fsi_device_release;
178 /* FSI slave support */
179 static int fsi_slave_calc_addr(struct fsi_slave *slave, uint32_t *addrp,
182 uint32_t addr = *addrp;
185 if (addr > slave->size)
188 /* For 23 bit addressing, we encode the extra two bits in the slave
189 * id (and the slave's actual ID needs to be 0).
191 if (addr > 0x1fffff) {
194 id = (addr >> 21) & 0x3;
203 static int fsi_slave_report_and_clear_errors(struct fsi_slave *slave)
205 struct fsi_master *master = slave->master;
213 rc = fsi_master_read(master, link, id, FSI_SLAVE_BASE + FSI_SISC,
218 rc = fsi_master_read(master, link, id, FSI_SLAVE_BASE + FSI_SSTAT,
219 &stat, sizeof(stat));
223 dev_dbg(&slave->dev, "status: 0x%08x, sisc: 0x%08x\n",
224 be32_to_cpu(stat), be32_to_cpu(irq));
226 /* clear interrupts */
227 return fsi_master_write(master, link, id, FSI_SLAVE_BASE + FSI_SISC,
231 /* Encode slave local bus echo delay */
232 static inline uint32_t fsi_smode_echodly(int x)
234 return (x & FSI_SMODE_ED_MASK) << FSI_SMODE_ED_SHIFT;
237 /* Encode slave local bus send delay */
238 static inline uint32_t fsi_smode_senddly(int x)
240 return (x & FSI_SMODE_SD_MASK) << FSI_SMODE_SD_SHIFT;
243 /* Encode slave local bus clock rate ratio */
244 static inline uint32_t fsi_smode_lbcrr(int x)
246 return (x & FSI_SMODE_LBCRR_MASK) << FSI_SMODE_LBCRR_SHIFT;
249 /* Encode slave ID */
250 static inline uint32_t fsi_smode_sid(int x)
252 return (x & FSI_SMODE_SID_MASK) << FSI_SMODE_SID_SHIFT;
255 static uint32_t fsi_slave_smode(int id, u8 t_senddly, u8 t_echodly)
257 return FSI_SMODE_WSC | FSI_SMODE_ECRC
259 | fsi_smode_echodly(t_echodly - 1) | fsi_smode_senddly(t_senddly - 1)
260 | fsi_smode_lbcrr(0x8);
263 static int fsi_slave_set_smode(struct fsi_slave *slave)
268 /* set our smode register with the slave ID field to 0; this enables
269 * extended slave addressing
271 smode = fsi_slave_smode(slave->id, slave->t_send_delay, slave->t_echo_delay);
272 data = cpu_to_be32(smode);
274 return fsi_master_write(slave->master, slave->link, slave->id,
275 FSI_SLAVE_BASE + FSI_SMODE,
276 &data, sizeof(data));
279 static int fsi_slave_handle_error(struct fsi_slave *slave, bool write,
280 uint32_t addr, size_t size)
282 struct fsi_master *master = slave->master;
285 uint8_t id, send_delay, echo_delay;
293 dev_dbg(&slave->dev, "handling error on %s to 0x%08x[%zd]",
294 write ? "write" : "read", addr, size);
296 /* try a simple clear of error conditions, which may fail if we've lost
297 * communication with the slave
299 rc = fsi_slave_report_and_clear_errors(slave);
303 /* send a TERM and retry */
305 rc = master->term(master, link, id);
307 rc = fsi_master_read(master, link, id, 0,
310 rc = fsi_slave_report_and_clear_errors(slave);
316 send_delay = slave->t_send_delay;
317 echo_delay = slave->t_echo_delay;
319 /* getting serious, reset the slave via BREAK */
320 rc = fsi_master_break(master, link);
324 slave->t_send_delay = send_delay;
325 slave->t_echo_delay = echo_delay;
327 rc = fsi_slave_set_smode(slave);
331 if (master->link_config)
332 master->link_config(master, link,
334 slave->t_echo_delay);
336 return fsi_slave_report_and_clear_errors(slave);
339 int fsi_slave_read(struct fsi_slave *slave, uint32_t addr,
340 void *val, size_t size)
342 uint8_t id = slave->id;
345 rc = fsi_slave_calc_addr(slave, &addr, &id);
349 for (i = 0; i < slave_retries; i++) {
350 rc = fsi_master_read(slave->master, slave->link,
351 id, addr, val, size);
355 err_rc = fsi_slave_handle_error(slave, false, addr, size);
362 EXPORT_SYMBOL_GPL(fsi_slave_read);
364 int fsi_slave_write(struct fsi_slave *slave, uint32_t addr,
365 const void *val, size_t size)
367 uint8_t id = slave->id;
370 rc = fsi_slave_calc_addr(slave, &addr, &id);
374 for (i = 0; i < slave_retries; i++) {
375 rc = fsi_master_write(slave->master, slave->link,
376 id, addr, val, size);
380 err_rc = fsi_slave_handle_error(slave, true, addr, size);
387 EXPORT_SYMBOL_GPL(fsi_slave_write);
389 extern int fsi_slave_claim_range(struct fsi_slave *slave,
390 uint32_t addr, uint32_t size)
392 if (addr + size < addr)
395 if (addr + size > slave->size)
398 /* todo: check for overlapping claims */
401 EXPORT_SYMBOL_GPL(fsi_slave_claim_range);
403 extern void fsi_slave_release_range(struct fsi_slave *slave,
404 uint32_t addr, uint32_t size)
407 EXPORT_SYMBOL_GPL(fsi_slave_release_range);
409 static bool fsi_device_node_matches(struct device *dev, struct device_node *np,
410 uint32_t addr, uint32_t size)
412 unsigned int len, na, ns;
416 na = of_n_addr_cells(np);
417 ns = of_n_size_cells(np);
419 if (na != 1 || ns != 1)
422 prop = of_get_property(np, "reg", &len);
423 if (!prop || len != 8)
426 if (of_read_number(prop, 1) != addr)
429 psize = of_read_number(prop + 1, 1);
432 "node %s matches probed address, but not size (got 0x%x, expected 0x%x)",
433 of_node_full_name(np), psize, size);
439 /* Find a matching node for the slave engine at @address, using @size bytes
440 * of space. Returns NULL if not found, or a matching node with refcount
441 * already incremented.
443 static struct device_node *fsi_device_find_of_node(struct fsi_device *dev)
445 struct device_node *parent, *np;
447 parent = dev_of_node(&dev->slave->dev);
451 for_each_child_of_node(parent, np) {
452 if (fsi_device_node_matches(&dev->dev, np,
453 dev->addr, dev->size))
460 static int fsi_slave_scan(struct fsi_slave *slave)
462 uint32_t engine_addr;
468 * We keep the peek mode and slave engines for the core; so start
469 * at the third slot in the configuration table. We also need to
470 * skip the chip ID entry at the start of the address space.
472 engine_addr = engine_page_size * 3;
473 for (i = 2; i < engine_page_size / sizeof(uint32_t); i++) {
474 uint8_t slots, version, type, crc;
475 struct fsi_device *dev;
479 rc = fsi_slave_read(slave, (i + 1) * sizeof(data),
480 &data, sizeof(data));
482 dev_warn(&slave->dev,
483 "error reading slave registers\n");
486 conf = be32_to_cpu(data);
488 crc = crc4(0, conf, 32);
490 dev_warn(&slave->dev,
491 "crc error in slave register at 0x%04x\n",
496 slots = (conf & FSI_SLAVE_CONF_SLOTS_MASK)
497 >> FSI_SLAVE_CONF_SLOTS_SHIFT;
498 version = (conf & FSI_SLAVE_CONF_VERSION_MASK)
499 >> FSI_SLAVE_CONF_VERSION_SHIFT;
500 type = (conf & FSI_SLAVE_CONF_TYPE_MASK)
501 >> FSI_SLAVE_CONF_TYPE_SHIFT;
504 * Unused address areas are marked by a zero type value; this
505 * skips the defined address areas
507 if (type != 0 && slots != 0) {
510 dev = fsi_create_device(slave);
515 dev->engine_type = type;
516 dev->version = version;
518 dev->addr = engine_addr;
519 dev->size = slots * engine_page_size;
522 "engine[%i]: type %x, version %x, addr %x size %x\n",
523 dev->unit, dev->engine_type, version,
524 dev->addr, dev->size);
526 dev_set_name(&dev->dev, "%02x:%02x:%02x:%02x",
527 slave->master->idx, slave->link,
529 dev->dev.of_node = fsi_device_find_of_node(dev);
531 rc = device_register(&dev->dev);
533 dev_warn(&slave->dev, "add failed: %d\n", rc);
534 put_device(&dev->dev);
538 engine_addr += slots * engine_page_size;
540 if (!(conf & FSI_SLAVE_CONF_NEXT_MASK))
547 static ssize_t fsi_slave_sysfs_raw_read(struct file *file,
548 struct kobject *kobj, struct bin_attribute *attr, char *buf,
549 loff_t off, size_t count)
551 struct fsi_slave *slave = to_fsi_slave(kobj_to_dev(kobj));
552 size_t total_len, read_len;
558 if (off > 0xffffffff || count > 0xffffffff || off + count > 0xffffffff)
561 for (total_len = 0; total_len < count; total_len += read_len) {
562 read_len = min_t(size_t, count, 4);
563 read_len -= off & 0x3;
565 rc = fsi_slave_read(slave, off, buf + total_len, read_len);
575 static ssize_t fsi_slave_sysfs_raw_write(struct file *file,
576 struct kobject *kobj, struct bin_attribute *attr,
577 char *buf, loff_t off, size_t count)
579 struct fsi_slave *slave = to_fsi_slave(kobj_to_dev(kobj));
580 size_t total_len, write_len;
586 if (off > 0xffffffff || count > 0xffffffff || off + count > 0xffffffff)
589 for (total_len = 0; total_len < count; total_len += write_len) {
590 write_len = min_t(size_t, count, 4);
591 write_len -= off & 0x3;
593 rc = fsi_slave_write(slave, off, buf + total_len, write_len);
603 static const struct bin_attribute fsi_slave_raw_attr = {
609 .read = fsi_slave_sysfs_raw_read,
610 .write = fsi_slave_sysfs_raw_write,
613 static void fsi_slave_release(struct device *dev)
615 struct fsi_slave *slave = to_fsi_slave(dev);
617 fsi_free_minor(slave->dev.devt);
618 of_node_put(dev->of_node);
622 static bool fsi_slave_node_matches(struct device_node *np,
623 int link, uint8_t id)
625 unsigned int len, na, ns;
628 na = of_n_addr_cells(np);
629 ns = of_n_size_cells(np);
631 /* Ensure we have the correct format for addresses and sizes in
634 if (na != 2 || ns != 0)
637 prop = of_get_property(np, "reg", &len);
638 if (!prop || len != 8)
641 return (of_read_number(prop, 1) == link) &&
642 (of_read_number(prop + 1, 1) == id);
645 /* Find a matching node for the slave at (link, id). Returns NULL if none
646 * found, or a matching node with refcount already incremented.
648 static struct device_node *fsi_slave_find_of_node(struct fsi_master *master,
649 int link, uint8_t id)
651 struct device_node *parent, *np;
653 parent = dev_of_node(&master->dev);
657 for_each_child_of_node(parent, np) {
658 if (fsi_slave_node_matches(np, link, id))
665 static ssize_t cfam_read(struct file *filep, char __user *buf, size_t count,
668 struct fsi_slave *slave = filep->private_data;
669 size_t total_len, read_len;
670 loff_t off = *offset;
676 if (off > 0xffffffff || count > 0xffffffff || off + count > 0xffffffff)
679 for (total_len = 0; total_len < count; total_len += read_len) {
682 read_len = min_t(size_t, count, 4);
683 read_len -= off & 0x3;
685 rc = fsi_slave_read(slave, off, &data, read_len);
688 rc = copy_to_user(buf + total_len, &data, read_len);
701 static ssize_t cfam_write(struct file *filep, const char __user *buf,
702 size_t count, loff_t *offset)
704 struct fsi_slave *slave = filep->private_data;
705 size_t total_len, write_len;
706 loff_t off = *offset;
713 if (off > 0xffffffff || count > 0xffffffff || off + count > 0xffffffff)
716 for (total_len = 0; total_len < count; total_len += write_len) {
719 write_len = min_t(size_t, count, 4);
720 write_len -= off & 0x3;
722 rc = copy_from_user(&data, buf + total_len, write_len);
727 rc = fsi_slave_write(slave, off, &data, write_len);
738 static loff_t cfam_llseek(struct file *file, loff_t offset, int whence)
744 file->f_pos = offset;
753 static int cfam_open(struct inode *inode, struct file *file)
755 struct fsi_slave *slave = container_of(inode->i_cdev, struct fsi_slave, cdev);
757 file->private_data = slave;
762 static const struct file_operations cfam_fops = {
763 .owner = THIS_MODULE,
765 .llseek = cfam_llseek,
770 static ssize_t send_term_store(struct device *dev,
771 struct device_attribute *attr,
772 const char *buf, size_t count)
774 struct fsi_slave *slave = to_fsi_slave(dev);
775 struct fsi_master *master = slave->master;
780 master->term(master, slave->link, slave->id);
784 static DEVICE_ATTR_WO(send_term);
786 static ssize_t slave_send_echo_show(struct device *dev,
787 struct device_attribute *attr,
790 struct fsi_slave *slave = to_fsi_slave(dev);
792 return sprintf(buf, "%u\n", slave->t_send_delay);
795 static ssize_t slave_send_echo_store(struct device *dev,
796 struct device_attribute *attr, const char *buf, size_t count)
798 struct fsi_slave *slave = to_fsi_slave(dev);
799 struct fsi_master *master = slave->master;
803 if (kstrtoul(buf, 0, &val) < 0)
806 if (val < 1 || val > 16)
809 if (!master->link_config)
812 /* Current HW mandates that send and echo delay are identical */
813 slave->t_send_delay = val;
814 slave->t_echo_delay = val;
816 rc = fsi_slave_set_smode(slave);
819 if (master->link_config)
820 master->link_config(master, slave->link,
822 slave->t_echo_delay);
827 static DEVICE_ATTR(send_echo_delays, 0600,
828 slave_send_echo_show, slave_send_echo_store);
830 static ssize_t chip_id_show(struct device *dev,
831 struct device_attribute *attr,
834 struct fsi_slave *slave = to_fsi_slave(dev);
836 return sprintf(buf, "%d\n", slave->chip_id);
839 static DEVICE_ATTR_RO(chip_id);
841 static ssize_t cfam_id_show(struct device *dev,
842 struct device_attribute *attr,
845 struct fsi_slave *slave = to_fsi_slave(dev);
847 return sprintf(buf, "0x%x\n", slave->cfam_id);
850 static DEVICE_ATTR_RO(cfam_id);
852 static struct attribute *cfam_attr[] = {
853 &dev_attr_send_echo_delays.attr,
854 &dev_attr_chip_id.attr,
855 &dev_attr_cfam_id.attr,
856 &dev_attr_send_term.attr,
860 static const struct attribute_group cfam_attr_group = {
864 static const struct attribute_group *cfam_attr_groups[] = {
869 static char *cfam_devnode(struct device *dev, umode_t *mode,
870 kuid_t *uid, kgid_t *gid)
872 struct fsi_slave *slave = to_fsi_slave(dev);
874 #ifdef CONFIG_FSI_NEW_DEV_NODE
875 return kasprintf(GFP_KERNEL, "fsi/cfam%d", slave->cdev_idx);
877 return kasprintf(GFP_KERNEL, "cfam%d", slave->cdev_idx);
881 static const struct device_type cfam_type = {
883 .devnode = cfam_devnode,
884 .groups = cfam_attr_groups
887 static char *fsi_cdev_devnode(struct device *dev, umode_t *mode,
888 kuid_t *uid, kgid_t *gid)
890 #ifdef CONFIG_FSI_NEW_DEV_NODE
891 return kasprintf(GFP_KERNEL, "fsi/%s", dev_name(dev));
893 return kasprintf(GFP_KERNEL, "%s", dev_name(dev));
897 const struct device_type fsi_cdev_type = {
899 .devnode = fsi_cdev_devnode,
901 EXPORT_SYMBOL_GPL(fsi_cdev_type);
903 /* Backward compatible /dev/ numbering in "old style" mode */
904 static int fsi_adjust_index(int index)
906 #ifdef CONFIG_FSI_NEW_DEV_NODE
913 static int __fsi_get_new_minor(struct fsi_slave *slave, enum fsi_dev_type type,
914 dev_t *out_dev, int *out_index)
916 int cid = slave->chip_id;
919 /* Check if we qualify for legacy numbering */
920 if (cid >= 0 && cid < 16 && type < 4) {
921 /* Try reserving the legacy number */
922 id = (cid << 4) | type;
923 id = ida_simple_get(&fsi_minor_ida, id, id + 1, GFP_KERNEL);
925 *out_index = fsi_adjust_index(cid);
926 *out_dev = fsi_base_dev + id;
932 /* Fallback to non-legacy allocation */
934 id = ida_simple_get(&fsi_minor_ida, FSI_CHAR_LEGACY_TOP,
935 FSI_CHAR_MAX_DEVICES, GFP_KERNEL);
938 *out_index = fsi_adjust_index(id);
939 *out_dev = fsi_base_dev + id;
943 int fsi_get_new_minor(struct fsi_device *fdev, enum fsi_dev_type type,
944 dev_t *out_dev, int *out_index)
946 return __fsi_get_new_minor(fdev->slave, type, out_dev, out_index);
948 EXPORT_SYMBOL_GPL(fsi_get_new_minor);
950 void fsi_free_minor(dev_t dev)
952 ida_simple_remove(&fsi_minor_ida, MINOR(dev));
954 EXPORT_SYMBOL_GPL(fsi_free_minor);
956 static int fsi_slave_init(struct fsi_master *master, int link, uint8_t id)
959 struct fsi_slave *slave;
964 /* Currently, we only support single slaves on a link, and use the
965 * full 23-bit address range
970 rc = fsi_master_read(master, link, id, 0, &data, sizeof(data));
972 dev_dbg(&master->dev, "can't read slave %02x:%02x %d\n",
976 cfam_id = be32_to_cpu(data);
978 crc = crc4(0, cfam_id, 32);
980 dev_warn(&master->dev, "slave %02x:%02x invalid cfam id CRC!\n",
985 dev_dbg(&master->dev, "fsi: found chip %08x at %02x:%02x:%02x\n",
986 cfam_id, master->idx, link, id);
988 /* If we're behind a master that doesn't provide a self-running bus
989 * clock, put the slave into async mode
991 if (master->flags & FSI_MASTER_FLAG_SWCLOCK) {
992 llmode = cpu_to_be32(FSI_LLMODE_ASYNC);
993 rc = fsi_master_write(master, link, id,
994 FSI_SLAVE_BASE + FSI_LLMODE,
995 &llmode, sizeof(llmode));
997 dev_warn(&master->dev,
998 "can't set llmode on slave:%02x:%02x %d\n",
1002 /* We can communicate with a slave; create the slave device and
1005 slave = kzalloc(sizeof(*slave), GFP_KERNEL);
1009 dev_set_name(&slave->dev, "slave@%02x:%02x", link, id);
1010 slave->dev.type = &cfam_type;
1011 slave->dev.parent = &master->dev;
1012 slave->dev.of_node = fsi_slave_find_of_node(master, link, id);
1013 slave->dev.release = fsi_slave_release;
1014 device_initialize(&slave->dev);
1015 slave->cfam_id = cfam_id;
1016 slave->master = master;
1019 slave->size = FSI_SLAVE_SIZE_23b;
1020 slave->t_send_delay = 16;
1021 slave->t_echo_delay = 16;
1023 /* Get chip ID if any */
1024 slave->chip_id = -1;
1025 if (slave->dev.of_node) {
1027 if (!of_property_read_u32(slave->dev.of_node, "chip-id", &prop))
1028 slave->chip_id = prop;
1032 rc = fsi_slave_set_smode(slave);
1034 dev_warn(&master->dev,
1035 "can't set smode on slave:%02x:%02x %d\n",
1040 /* Allocate a minor in the FSI space */
1041 rc = __fsi_get_new_minor(slave, fsi_dev_cfam, &slave->dev.devt,
1046 /* Create chardev for userspace access */
1047 cdev_init(&slave->cdev, &cfam_fops);
1048 rc = cdev_device_add(&slave->cdev, &slave->dev);
1050 dev_err(&slave->dev, "Error %d creating slave device\n", rc);
1054 /* Now that we have the cdev registered with the core, any fatal
1055 * failures beyond this point will need to clean up through
1056 * cdev_device_del(). Fortunately though, nothing past here is fatal.
1059 if (master->link_config)
1060 master->link_config(master, link,
1061 slave->t_send_delay,
1062 slave->t_echo_delay);
1064 /* Legacy raw file -> to be removed */
1065 rc = device_create_bin_file(&slave->dev, &fsi_slave_raw_attr);
1067 dev_warn(&slave->dev, "failed to create raw attr: %d\n", rc);
1070 rc = fsi_slave_scan(slave);
1072 dev_dbg(&master->dev, "failed during slave scan with: %d\n",
1078 fsi_free_minor(slave->dev.devt);
1080 of_node_put(slave->dev.of_node);
1085 /* FSI master support */
1086 static int fsi_check_access(uint32_t addr, size_t size)
1091 } else if (size == 2) {
1094 } else if (size != 1)
1100 static int fsi_master_read(struct fsi_master *master, int link,
1101 uint8_t slave_id, uint32_t addr, void *val, size_t size)
1105 trace_fsi_master_read(master, link, slave_id, addr, size);
1107 rc = fsi_check_access(addr, size);
1109 rc = master->read(master, link, slave_id, addr, val, size);
1111 trace_fsi_master_rw_result(master, link, slave_id, addr, size,
1117 static int fsi_master_write(struct fsi_master *master, int link,
1118 uint8_t slave_id, uint32_t addr, const void *val, size_t size)
1122 trace_fsi_master_write(master, link, slave_id, addr, size, val);
1124 rc = fsi_check_access(addr, size);
1126 rc = master->write(master, link, slave_id, addr, val, size);
1128 trace_fsi_master_rw_result(master, link, slave_id, addr, size,
1134 static int fsi_master_link_enable(struct fsi_master *master, int link)
1136 if (master->link_enable)
1137 return master->link_enable(master, link);
1143 * Issue a break command on this link
1145 static int fsi_master_break(struct fsi_master *master, int link)
1149 trace_fsi_master_break(master, link);
1151 if (master->send_break)
1152 rc = master->send_break(master, link);
1153 if (master->link_config)
1154 master->link_config(master, link, 16, 16);
1159 static int fsi_master_scan(struct fsi_master *master)
1163 for (link = 0; link < master->n_links; link++) {
1164 rc = fsi_master_link_enable(master, link);
1166 dev_dbg(&master->dev,
1167 "enable link %d failed: %d\n", link, rc);
1170 rc = fsi_master_break(master, link);
1172 dev_dbg(&master->dev,
1173 "break to link %d failed: %d\n", link, rc);
1177 fsi_slave_init(master, link, 0);
1183 static int fsi_slave_remove_device(struct device *dev, void *arg)
1185 device_unregister(dev);
1189 static int fsi_master_remove_slave(struct device *dev, void *arg)
1191 struct fsi_slave *slave = to_fsi_slave(dev);
1193 device_for_each_child(dev, NULL, fsi_slave_remove_device);
1194 cdev_device_del(&slave->cdev, &slave->dev);
1199 static void fsi_master_unscan(struct fsi_master *master)
1201 device_for_each_child(&master->dev, NULL, fsi_master_remove_slave);
1204 int fsi_master_rescan(struct fsi_master *master)
1208 mutex_lock(&master->scan_lock);
1209 fsi_master_unscan(master);
1210 rc = fsi_master_scan(master);
1211 mutex_unlock(&master->scan_lock);
1215 EXPORT_SYMBOL_GPL(fsi_master_rescan);
1217 static ssize_t master_rescan_store(struct device *dev,
1218 struct device_attribute *attr, const char *buf, size_t count)
1220 struct fsi_master *master = to_fsi_master(dev);
1223 rc = fsi_master_rescan(master);
1230 static DEVICE_ATTR(rescan, 0200, NULL, master_rescan_store);
1232 static ssize_t master_break_store(struct device *dev,
1233 struct device_attribute *attr, const char *buf, size_t count)
1235 struct fsi_master *master = to_fsi_master(dev);
1237 fsi_master_break(master, 0);
1242 static DEVICE_ATTR(break, 0200, NULL, master_break_store);
1244 int fsi_master_register(struct fsi_master *master)
1247 struct device_node *np;
1249 mutex_init(&master->scan_lock);
1250 master->idx = ida_simple_get(&master_ida, 0, INT_MAX, GFP_KERNEL);
1251 dev_set_name(&master->dev, "fsi%d", master->idx);
1253 rc = device_register(&master->dev);
1255 ida_simple_remove(&master_ida, master->idx);
1259 rc = device_create_file(&master->dev, &dev_attr_rescan);
1261 device_del(&master->dev);
1262 ida_simple_remove(&master_ida, master->idx);
1266 rc = device_create_file(&master->dev, &dev_attr_break);
1268 device_del(&master->dev);
1269 ida_simple_remove(&master_ida, master->idx);
1273 np = dev_of_node(&master->dev);
1274 if (!of_property_read_bool(np, "no-scan-on-init")) {
1275 mutex_lock(&master->scan_lock);
1276 fsi_master_scan(master);
1277 mutex_unlock(&master->scan_lock);
1282 EXPORT_SYMBOL_GPL(fsi_master_register);
1284 void fsi_master_unregister(struct fsi_master *master)
1286 if (master->idx >= 0) {
1287 ida_simple_remove(&master_ida, master->idx);
1291 mutex_lock(&master->scan_lock);
1292 fsi_master_unscan(master);
1293 mutex_unlock(&master->scan_lock);
1294 device_unregister(&master->dev);
1296 EXPORT_SYMBOL_GPL(fsi_master_unregister);
1298 /* FSI core & Linux bus type definitions */
1300 static int fsi_bus_match(struct device *dev, struct device_driver *drv)
1302 struct fsi_device *fsi_dev = to_fsi_dev(dev);
1303 struct fsi_driver *fsi_drv = to_fsi_drv(drv);
1304 const struct fsi_device_id *id;
1306 if (!fsi_drv->id_table)
1309 for (id = fsi_drv->id_table; id->engine_type; id++) {
1310 if (id->engine_type != fsi_dev->engine_type)
1312 if (id->version == FSI_VERSION_ANY ||
1313 id->version == fsi_dev->version)
1320 int fsi_driver_register(struct fsi_driver *fsi_drv)
1324 if (!fsi_drv->id_table)
1327 return driver_register(&fsi_drv->drv);
1329 EXPORT_SYMBOL_GPL(fsi_driver_register);
1331 void fsi_driver_unregister(struct fsi_driver *fsi_drv)
1333 driver_unregister(&fsi_drv->drv);
1335 EXPORT_SYMBOL_GPL(fsi_driver_unregister);
1337 struct bus_type fsi_bus_type = {
1339 .match = fsi_bus_match,
1341 EXPORT_SYMBOL_GPL(fsi_bus_type);
1343 static int __init fsi_init(void)
1347 rc = alloc_chrdev_region(&fsi_base_dev, 0, FSI_CHAR_MAX_DEVICES, "fsi");
1350 rc = bus_register(&fsi_bus_type);
1356 unregister_chrdev_region(fsi_base_dev, FSI_CHAR_MAX_DEVICES);
1359 postcore_initcall(fsi_init);
1361 static void fsi_exit(void)
1363 bus_unregister(&fsi_bus_type);
1364 unregister_chrdev_region(fsi_base_dev, FSI_CHAR_MAX_DEVICES);
1365 ida_destroy(&fsi_minor_ida);
1367 module_exit(fsi_exit);
1368 module_param(discard_errors, int, 0664);
1369 MODULE_LICENSE("GPL");
1370 MODULE_PARM_DESC(discard_errors, "Don't invoke error handling on bus accesses");