linux/drivers/macintosh/via-macii.c
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00

551 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Device driver for the via ADB on (many) Mac II-class machines
*
* Based on the original ADB keyboard handler Copyright (c) 1997 Alan Cox
* Also derived from code Copyright (C) 1996 Paul Mackerras.
*
* With various updates provided over the years by Michael Schmitz,
* Guideo Koerber and others.
*
* Rewrite for Unified ADB by Joshua M. Thompson (funaho@jurai.org)
*
* 1999-08-02 (jmt) - Initial rewrite for Unified ADB.
* 2000-03-29 Tony Mantler <tonym@mac.linux-m68k.org>
* - Big overhaul, should actually work now.
* 2006-12-31 Finn Thain - Another overhaul.
*
* Suggested reading:
* Inside Macintosh, ch. 5 ADB Manager
* Guide to the Macinstosh Family Hardware, ch. 8 Apple Desktop Bus
* Rockwell R6522 VIA datasheet
*
* Apple's "ADB Analyzer" bus sniffer is invaluable:
* ftp://ftp.apple.com/developer/Tool_Chest/Devices_-_Hardware/Apple_Desktop_Bus/
*/
#include <stdarg.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/adb.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <asm/macintosh.h>
#include <asm/macints.h>
#include <asm/mac_via.h>
static volatile unsigned char *via;
/* VIA registers - spaced 0x200 bytes apart */
#define RS 0x200 /* skip between registers */
#define B 0 /* B-side data */
#define A RS /* A-side data */
#define DIRB (2*RS) /* B-side direction (1=output) */
#define DIRA (3*RS) /* A-side direction (1=output) */
#define T1CL (4*RS) /* Timer 1 ctr/latch (low 8 bits) */
#define T1CH (5*RS) /* Timer 1 counter (high 8 bits) */
#define T1LL (6*RS) /* Timer 1 latch (low 8 bits) */
#define T1LH (7*RS) /* Timer 1 latch (high 8 bits) */
#define T2CL (8*RS) /* Timer 2 ctr/latch (low 8 bits) */
#define T2CH (9*RS) /* Timer 2 counter (high 8 bits) */
#define SR (10*RS) /* Shift register */
#define ACR (11*RS) /* Auxiliary control register */
#define PCR (12*RS) /* Peripheral control register */
#define IFR (13*RS) /* Interrupt flag register */
#define IER (14*RS) /* Interrupt enable register */
#define ANH (15*RS) /* A-side data, no handshake */
/* Bits in B data register: all active low */
#define CTLR_IRQ 0x08 /* Controller rcv status (input) */
#define ST_MASK 0x30 /* mask for selecting ADB state bits */
/* Bits in ACR */
#define SR_CTRL 0x1c /* Shift register control bits */
#define SR_EXT 0x0c /* Shift on external clock */
#define SR_OUT 0x10 /* Shift out if 1 */
/* Bits in IFR and IER */
#define IER_SET 0x80 /* set bits in IER */
#define IER_CLR 0 /* clear bits in IER */
#define SR_INT 0x04 /* Shift register full/empty */
/* ADB transaction states according to GMHW */
#define ST_CMD 0x00 /* ADB state: command byte */
#define ST_EVEN 0x10 /* ADB state: even data byte */
#define ST_ODD 0x20 /* ADB state: odd data byte */
#define ST_IDLE 0x30 /* ADB state: idle, nothing to send */
static int macii_init_via(void);
static void macii_start(void);
static irqreturn_t macii_interrupt(int irq, void *arg);
static void macii_queue_poll(void);
static int macii_probe(void);
static int macii_init(void);
static int macii_send_request(struct adb_request *req, int sync);
static int macii_write(struct adb_request *req);
static int macii_autopoll(int devs);
static void macii_poll(void);
static int macii_reset_bus(void);
struct adb_driver via_macii_driver = {
"Mac II",
macii_probe,
macii_init,
macii_send_request,
macii_autopoll,
macii_poll,
macii_reset_bus
};
static enum macii_state {
idle,
sending,
reading,
read_done,
} macii_state;
static struct adb_request *current_req; /* first request struct in the queue */
static struct adb_request *last_req; /* last request struct in the queue */
static unsigned char reply_buf[16]; /* storage for autopolled replies */
static unsigned char *reply_ptr; /* next byte in reply_buf or req->reply */
static int reading_reply; /* store reply in reply_buf else req->reply */
static int data_index; /* index of the next byte to send from req->data */
static int reply_len; /* number of bytes received in reply_buf or req->reply */
static int status; /* VIA's ADB status bits captured upon interrupt */
static int last_status; /* status bits as at previous interrupt */
static int srq_asserted; /* have to poll for the device that asserted it */
static int command_byte; /* the most recent command byte transmitted */
static int autopoll_devs; /* bits set are device addresses to be polled */
/* Sanity check for request queue. Doesn't check for cycles. */
static int request_is_queued(struct adb_request *req) {
struct adb_request *cur;
unsigned long flags;
local_irq_save(flags);
cur = current_req;
while (cur) {
if (cur == req) {
local_irq_restore(flags);
return 1;
}
cur = cur->next;
}
local_irq_restore(flags);
return 0;
}
/* Check for MacII style ADB */
static int macii_probe(void)
{
if (macintosh_config->adb_type != MAC_ADB_II) return -ENODEV;
via = via1;
printk("adb: Mac II ADB Driver v1.0 for Unified ADB\n");
return 0;
}
/* Initialize the driver */
int macii_init(void)
{
unsigned long flags;
int err;
local_irq_save(flags);
err = macii_init_via();
if (err) goto out;
err = request_irq(IRQ_MAC_ADB, macii_interrupt, 0, "ADB",
macii_interrupt);
if (err) goto out;
macii_state = idle;
out:
local_irq_restore(flags);
return err;
}
/* initialize the hardware */
static int macii_init_via(void)
{
unsigned char x;
/* We want CTLR_IRQ as input and ST_EVEN | ST_ODD as output lines. */
via[DIRB] = (via[DIRB] | ST_EVEN | ST_ODD) & ~CTLR_IRQ;
/* Set up state: idle */
via[B] |= ST_IDLE;
last_status = via[B] & (ST_MASK|CTLR_IRQ);
/* Shift register on input */
via[ACR] = (via[ACR] & ~SR_CTRL) | SR_EXT;
/* Wipe any pending data and int */
x = via[SR];
return 0;
}
/* Send an ADB poll (Talk Register 0 command prepended to the request queue) */
static void macii_queue_poll(void)
{
/* No point polling the active device as it will never assert SRQ, so
* poll the next device in the autopoll list. This could leave us
* stuck in a polling loop if an unprobed device is asserting SRQ.
* In theory, that could only happen if a device was plugged in after
* probing started. Unplugging it again will break the cycle.
* (Simply polling the next higher device often ends up polling almost
* every device (after wrapping around), which takes too long.)
*/
int device_mask;
int next_device;
static struct adb_request req;
if (!autopoll_devs) return;
device_mask = (1 << (((command_byte & 0xF0) >> 4) + 1)) - 1;
if (autopoll_devs & ~device_mask)
next_device = ffs(autopoll_devs & ~device_mask) - 1;
else
next_device = ffs(autopoll_devs) - 1;
BUG_ON(request_is_queued(&req));
adb_request(&req, NULL, ADBREQ_NOSEND, 1,
ADB_READREG(next_device, 0));
req.sent = 0;
req.complete = 0;
req.reply_len = 0;
req.next = current_req;
if (current_req != NULL) {
current_req = &req;
} else {
current_req = &req;
last_req = &req;
}
}
/* Send an ADB request; if sync, poll out the reply 'till it's done */
static int macii_send_request(struct adb_request *req, int sync)
{
int err;
unsigned long flags;
BUG_ON(request_is_queued(req));
local_irq_save(flags);
err = macii_write(req);
local_irq_restore(flags);
if (!err && sync) {
while (!req->complete) {
macii_poll();
}
BUG_ON(request_is_queued(req));
}
return err;
}
/* Send an ADB request (append to request queue) */
static int macii_write(struct adb_request *req)
{
if (req->nbytes < 2 || req->data[0] != ADB_PACKET || req->nbytes > 15) {
req->complete = 1;
return -EINVAL;
}
req->next = NULL;
req->sent = 0;
req->complete = 0;
req->reply_len = 0;
if (current_req != NULL) {
last_req->next = req;
last_req = req;
} else {
current_req = req;
last_req = req;
if (macii_state == idle) macii_start();
}
return 0;
}
/* Start auto-polling */
static int macii_autopoll(int devs)
{
static struct adb_request req;
unsigned long flags;
int err = 0;
/* bit 1 == device 1, and so on. */
autopoll_devs = devs & 0xFFFE;
if (!autopoll_devs) return 0;
local_irq_save(flags);
if (current_req == NULL) {
/* Send a Talk Reg 0. The controller will repeatedly transmit
* this as long as it is idle.
*/
adb_request(&req, NULL, ADBREQ_NOSEND, 1,
ADB_READREG(ffs(autopoll_devs) - 1, 0));
err = macii_write(&req);
}
local_irq_restore(flags);
return err;
}
static inline int need_autopoll(void) {
/* Was the last command Talk Reg 0
* and is the target on the autopoll list?
*/
if ((command_byte & 0x0F) == 0x0C &&
((1 << ((command_byte & 0xF0) >> 4)) & autopoll_devs))
return 0;
return 1;
}
/* Prod the chip without interrupts */
static void macii_poll(void)
{
disable_irq(IRQ_MAC_ADB);
macii_interrupt(0, NULL);
enable_irq(IRQ_MAC_ADB);
}
/* Reset the bus */
static int macii_reset_bus(void)
{
static struct adb_request req;
if (request_is_queued(&req))
return 0;
/* Command = 0, Address = ignored */
adb_request(&req, NULL, 0, 1, ADB_BUSRESET);
/* Don't want any more requests during the Global Reset low time. */
udelay(3000);
return 0;
}
/* Start sending ADB packet */
static void macii_start(void)
{
struct adb_request *req;
req = current_req;
BUG_ON(req == NULL);
BUG_ON(macii_state != idle);
/* Now send it. Be careful though, that first byte of the request
* is actually ADB_PACKET; the real data begins at index 1!
* And req->nbytes is the number of bytes of real data plus one.
*/
/* store command byte */
command_byte = req->data[1];
/* Output mode */
via[ACR] |= SR_OUT;
/* Load data */
via[SR] = req->data[1];
/* set ADB state to 'command' */
via[B] = (via[B] & ~ST_MASK) | ST_CMD;
macii_state = sending;
data_index = 2;
}
/*
* The notorious ADB interrupt handler - does all of the protocol handling.
* Relies on the ADB controller sending and receiving data, thereby
* generating shift register interrupts (SR_INT) for us. This means there has
* to be activity on the ADB bus. The chip will poll to achieve this.
*
* The basic ADB state machine was left unchanged from the original MacII code
* by Alan Cox, which was based on the CUDA driver for PowerMac.
* The syntax of the ADB status lines is totally different on MacII,
* though. MacII uses the states Command -> Even -> Odd -> Even ->...-> Idle
* for sending and Idle -> Even -> Odd -> Even ->...-> Idle for receiving.
* Start and end of a receive packet are signalled by asserting /IRQ on the
* interrupt line (/IRQ means the CTLR_IRQ bit in port B; not to be confused
* with the VIA shift register interrupt. /IRQ never actually interrupts the
* processor, it's just an ordinary input.)
*/
static irqreturn_t macii_interrupt(int irq, void *arg)
{
int x;
static int entered;
struct adb_request *req;
if (!arg) {
/* Clear the SR IRQ flag when polling. */
if (via[IFR] & SR_INT)
via[IFR] = SR_INT;
else
return IRQ_NONE;
}
BUG_ON(entered++);
last_status = status;
status = via[B] & (ST_MASK|CTLR_IRQ);
switch (macii_state) {
case idle:
if (reading_reply) {
reply_ptr = current_req->reply;
} else {
BUG_ON(current_req != NULL);
reply_ptr = reply_buf;
}
x = via[SR];
if ((status & CTLR_IRQ) && (x == 0xFF)) {
/* Bus timeout without SRQ sequence:
* data is "FF" while CTLR_IRQ is "H"
*/
reply_len = 0;
srq_asserted = 0;
macii_state = read_done;
} else {
macii_state = reading;
*reply_ptr = x;
reply_len = 1;
}
/* set ADB state = even for first data byte */
via[B] = (via[B] & ~ST_MASK) | ST_EVEN;
break;
case sending:
req = current_req;
if (data_index >= req->nbytes) {
req->sent = 1;
macii_state = idle;
if (req->reply_expected) {
reading_reply = 1;
} else {
req->complete = 1;
current_req = req->next;
if (req->done) (*req->done)(req);
if (current_req)
macii_start();
else
if (need_autopoll())
macii_autopoll(autopoll_devs);
}
if (macii_state == idle) {
/* reset to shift in */
via[ACR] &= ~SR_OUT;
x = via[SR];
/* set ADB state idle - might get SRQ */
via[B] = (via[B] & ~ST_MASK) | ST_IDLE;
}
} else {
via[SR] = req->data[data_index++];
if ( (via[B] & ST_MASK) == ST_CMD ) {
/* just sent the command byte, set to EVEN */
via[B] = (via[B] & ~ST_MASK) | ST_EVEN;
} else {
/* invert state bits, toggle ODD/EVEN */
via[B] ^= ST_MASK;
}
}
break;
case reading:
x = via[SR];
BUG_ON((status & ST_MASK) == ST_CMD ||
(status & ST_MASK) == ST_IDLE);
/* Bus timeout with SRQ sequence:
* data is "XX FF" while CTLR_IRQ is "L L"
* End of packet without SRQ sequence:
* data is "XX...YY 00" while CTLR_IRQ is "L...H L"
* End of packet SRQ sequence:
* data is "XX...YY 00" while CTLR_IRQ is "L...L L"
* (where XX is the first response byte and
* YY is the last byte of valid response data.)
*/
srq_asserted = 0;
if (!(status & CTLR_IRQ)) {
if (x == 0xFF) {
if (!(last_status & CTLR_IRQ)) {
macii_state = read_done;
reply_len = 0;
srq_asserted = 1;
}
} else if (x == 0x00) {
macii_state = read_done;
if (!(last_status & CTLR_IRQ))
srq_asserted = 1;
}
}
if (macii_state == reading) {
BUG_ON(reply_len > 15);
reply_ptr++;
*reply_ptr = x;
reply_len++;
}
/* invert state bits, toggle ODD/EVEN */
via[B] ^= ST_MASK;
break;
case read_done:
x = via[SR];
if (reading_reply) {
reading_reply = 0;
req = current_req;
req->reply_len = reply_len;
req->complete = 1;
current_req = req->next;
if (req->done) (*req->done)(req);
} else if (reply_len && autopoll_devs)
adb_input(reply_buf, reply_len, 0);
macii_state = idle;
/* SRQ seen before, initiate poll now */
if (srq_asserted)
macii_queue_poll();
if (current_req)
macii_start();
else
if (need_autopoll())
macii_autopoll(autopoll_devs);
if (macii_state == idle)
via[B] = (via[B] & ~ST_MASK) | ST_IDLE;
break;
default:
break;
}
entered--;
return IRQ_HANDLED;
}