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v3.1
  1/*
  2 * Driver for the ADB controller in the Mac I/O (Hydra) chip.
  3 */
  4#include <stdarg.h>
  5#include <linux/types.h>
  6#include <linux/errno.h>
  7#include <linux/kernel.h>
  8#include <linux/delay.h>
  9#include <linux/spinlock.h>
 10#include <linux/interrupt.h>
 11#include <asm/prom.h>
 12#include <linux/adb.h>
 13#include <asm/io.h>
 14#include <asm/pgtable.h>
 15#include <asm/hydra.h>
 16#include <asm/irq.h>
 17#include <asm/system.h>
 18#include <linux/init.h>
 19#include <linux/ioport.h>
 20
 21struct preg {
 22	unsigned char r;
 23	char pad[15];
 24};
 25
 26struct adb_regs {
 27	struct preg intr;
 28	struct preg data[9];
 29	struct preg intr_enb;
 30	struct preg dcount;
 31	struct preg error;
 32	struct preg ctrl;
 33	struct preg autopoll;
 34	struct preg active_hi;
 35	struct preg active_lo;
 36	struct preg test;
 37};
 38
 39/* Bits in intr and intr_enb registers */
 40#define DFB	1		/* data from bus */
 41#define TAG	2		/* transfer access grant */
 42
 43/* Bits in dcount register */
 44#define HMB	0x0f		/* how many bytes */
 45#define APD	0x10		/* auto-poll data */
 46
 47/* Bits in error register */
 48#define NRE	1		/* no response error */
 49#define DLE	2		/* data lost error */
 50
 51/* Bits in ctrl register */
 52#define TAR	1		/* transfer access request */
 53#define DTB	2		/* data to bus */
 54#define CRE	4		/* command response expected */
 55#define ADB_RST	8		/* ADB reset */
 56
 57/* Bits in autopoll register */
 58#define APE	1		/* autopoll enable */
 59
 60static volatile struct adb_regs __iomem *adb;
 61static struct adb_request *current_req, *last_req;
 62static DEFINE_SPINLOCK(macio_lock);
 63
 64static int macio_probe(void);
 65static int macio_init(void);
 66static irqreturn_t macio_adb_interrupt(int irq, void *arg);
 67static int macio_send_request(struct adb_request *req, int sync);
 68static int macio_adb_autopoll(int devs);
 69static void macio_adb_poll(void);
 70static int macio_adb_reset_bus(void);
 71
 72struct adb_driver macio_adb_driver = {
 73	"MACIO",
 74	macio_probe,
 75	macio_init,
 76	macio_send_request,
 77	/*macio_write,*/
 78	macio_adb_autopoll,
 79	macio_adb_poll,
 80	macio_adb_reset_bus
 81};
 82
 83int macio_probe(void)
 84{
 85	struct device_node *np;
 86
 87	np = of_find_compatible_node(NULL, "adb", "chrp,adb0");
 88	if (np) {
 89		of_node_put(np);
 90		return 0;
 91	}
 92	return -ENODEV;
 93}
 94
 95int macio_init(void)
 96{
 97	struct device_node *adbs;
 98	struct resource r;
 99	unsigned int irq;
100
101	adbs = of_find_compatible_node(NULL, "adb", "chrp,adb0");
102	if (adbs == 0)
103		return -ENXIO;
104
105	if (of_address_to_resource(adbs, 0, &r)) {
106		of_node_put(adbs);
107		return -ENXIO;
108	}
109	adb = ioremap(r.start, sizeof(struct adb_regs));
110
111	out_8(&adb->ctrl.r, 0);
112	out_8(&adb->intr.r, 0);
113	out_8(&adb->error.r, 0);
114	out_8(&adb->active_hi.r, 0xff); /* for now, set all devices active */
115	out_8(&adb->active_lo.r, 0xff);
116	out_8(&adb->autopoll.r, APE);
117
118	irq = irq_of_parse_and_map(adbs, 0);
119	of_node_put(adbs);
120	if (request_irq(irq, macio_adb_interrupt, 0, "ADB", (void *)0)) {
121		printk(KERN_ERR "ADB: can't get irq %d\n", irq);
122		return -EAGAIN;
123	}
124	out_8(&adb->intr_enb.r, DFB | TAG);
125
126	printk("adb: mac-io driver 1.0 for unified ADB\n");
127
128	return 0;
129}
130
131static int macio_adb_autopoll(int devs)
132{
133	unsigned long flags;
134	
135	spin_lock_irqsave(&macio_lock, flags);
136	out_8(&adb->active_hi.r, devs >> 8);
137	out_8(&adb->active_lo.r, devs);
138	out_8(&adb->autopoll.r, devs? APE: 0);
139	spin_unlock_irqrestore(&macio_lock, flags);
140	return 0;
141}
142
143static int macio_adb_reset_bus(void)
144{
145	unsigned long flags;
146	int timeout = 1000000;
147
148	/* Hrm... we may want to not lock interrupts for so
149	 * long ... oh well, who uses that chip anyway ? :)
150	 * That function will be seldom used during boot
151	 * on rare machines, so...
152	 */
153	spin_lock_irqsave(&macio_lock, flags);
154	out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | ADB_RST);
155	while ((in_8(&adb->ctrl.r) & ADB_RST) != 0) {
156		if (--timeout == 0) {
157			out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) & ~ADB_RST);
158			spin_unlock_irqrestore(&macio_lock, flags);
159			return -1;
160		}
161	}
162	spin_unlock_irqrestore(&macio_lock, flags);
163	return 0;
164}
165
166/* Send an ADB command */
167static int macio_send_request(struct adb_request *req, int sync)
168{
169	unsigned long flags;
170	int i;
171	
172	if (req->data[0] != ADB_PACKET)
173		return -EINVAL;
174	
175	for (i = 0; i < req->nbytes - 1; ++i)
176		req->data[i] = req->data[i+1];
177	--req->nbytes;
178	
179	req->next = NULL;
180	req->sent = 0;
181	req->complete = 0;
182	req->reply_len = 0;
183
184	spin_lock_irqsave(&macio_lock, flags);
185	if (current_req != 0) {
186		last_req->next = req;
187		last_req = req;
188	} else {
189		current_req = last_req = req;
190		out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
191	}
192	spin_unlock_irqrestore(&macio_lock, flags);
193	
194	if (sync) {
195		while (!req->complete)
196			macio_adb_poll();
197	}
198
199	return 0;
200}
201
202static irqreturn_t macio_adb_interrupt(int irq, void *arg)
203{
204	int i, n, err;
205	struct adb_request *req = NULL;
206	unsigned char ibuf[16];
207	int ibuf_len = 0;
208	int complete = 0;
209	int autopoll = 0;
210	int handled = 0;
211
212	spin_lock(&macio_lock);
213	if (in_8(&adb->intr.r) & TAG) {
214		handled = 1;
215		if ((req = current_req) != 0) {
216			/* put the current request in */
217			for (i = 0; i < req->nbytes; ++i)
218				out_8(&adb->data[i].r, req->data[i]);
219			out_8(&adb->dcount.r, req->nbytes & HMB);
220			req->sent = 1;
221			if (req->reply_expected) {
222				out_8(&adb->ctrl.r, DTB + CRE);
223			} else {
224				out_8(&adb->ctrl.r, DTB);
225				current_req = req->next;
226				complete = 1;
227				if (current_req)
228					out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
229			}
230		}
231		out_8(&adb->intr.r, 0);
232	}
233
234	if (in_8(&adb->intr.r) & DFB) {
235		handled = 1;
236		err = in_8(&adb->error.r);
237		if (current_req && current_req->sent) {
238			/* this is the response to a command */
239			req = current_req;
240			if (err == 0) {
241				req->reply_len = in_8(&adb->dcount.r) & HMB;
242				for (i = 0; i < req->reply_len; ++i)
243					req->reply[i] = in_8(&adb->data[i].r);
244			}
245			current_req = req->next;
246			complete = 1;
247			if (current_req)
248				out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
249		} else if (err == 0) {
250			/* autopoll data */
251			n = in_8(&adb->dcount.r) & HMB;
252			for (i = 0; i < n; ++i)
253				ibuf[i] = in_8(&adb->data[i].r);
254			ibuf_len = n;
255			autopoll = (in_8(&adb->dcount.r) & APD) != 0;
256		}
257		out_8(&adb->error.r, 0);
258		out_8(&adb->intr.r, 0);
259	}
260	spin_unlock(&macio_lock);
261	if (complete && req) {
262	    void (*done)(struct adb_request *) = req->done;
263	    mb();
264	    req->complete = 1;
265	    /* Here, we assume that if the request has a done member, the
266    	     * struct request will survive to setting req->complete to 1
267	     */
268	    if (done)
269		(*done)(req);
270	}
271	if (ibuf_len)
272		adb_input(ibuf, ibuf_len, autopoll);
273
274	return IRQ_RETVAL(handled);
275}
276
277static void macio_adb_poll(void)
278{
279	unsigned long flags;
280
281	local_irq_save(flags);
282	if (in_8(&adb->intr.r) != 0)
283		macio_adb_interrupt(0, NULL);
284	local_irq_restore(flags);
285}
v3.5.6
  1/*
  2 * Driver for the ADB controller in the Mac I/O (Hydra) chip.
  3 */
  4#include <stdarg.h>
  5#include <linux/types.h>
  6#include <linux/errno.h>
  7#include <linux/kernel.h>
  8#include <linux/delay.h>
  9#include <linux/spinlock.h>
 10#include <linux/interrupt.h>
 11#include <asm/prom.h>
 12#include <linux/adb.h>
 13#include <asm/io.h>
 14#include <asm/pgtable.h>
 15#include <asm/hydra.h>
 16#include <asm/irq.h>
 
 17#include <linux/init.h>
 18#include <linux/ioport.h>
 19
 20struct preg {
 21	unsigned char r;
 22	char pad[15];
 23};
 24
 25struct adb_regs {
 26	struct preg intr;
 27	struct preg data[9];
 28	struct preg intr_enb;
 29	struct preg dcount;
 30	struct preg error;
 31	struct preg ctrl;
 32	struct preg autopoll;
 33	struct preg active_hi;
 34	struct preg active_lo;
 35	struct preg test;
 36};
 37
 38/* Bits in intr and intr_enb registers */
 39#define DFB	1		/* data from bus */
 40#define TAG	2		/* transfer access grant */
 41
 42/* Bits in dcount register */
 43#define HMB	0x0f		/* how many bytes */
 44#define APD	0x10		/* auto-poll data */
 45
 46/* Bits in error register */
 47#define NRE	1		/* no response error */
 48#define DLE	2		/* data lost error */
 49
 50/* Bits in ctrl register */
 51#define TAR	1		/* transfer access request */
 52#define DTB	2		/* data to bus */
 53#define CRE	4		/* command response expected */
 54#define ADB_RST	8		/* ADB reset */
 55
 56/* Bits in autopoll register */
 57#define APE	1		/* autopoll enable */
 58
 59static volatile struct adb_regs __iomem *adb;
 60static struct adb_request *current_req, *last_req;
 61static DEFINE_SPINLOCK(macio_lock);
 62
 63static int macio_probe(void);
 64static int macio_init(void);
 65static irqreturn_t macio_adb_interrupt(int irq, void *arg);
 66static int macio_send_request(struct adb_request *req, int sync);
 67static int macio_adb_autopoll(int devs);
 68static void macio_adb_poll(void);
 69static int macio_adb_reset_bus(void);
 70
 71struct adb_driver macio_adb_driver = {
 72	"MACIO",
 73	macio_probe,
 74	macio_init,
 75	macio_send_request,
 76	/*macio_write,*/
 77	macio_adb_autopoll,
 78	macio_adb_poll,
 79	macio_adb_reset_bus
 80};
 81
 82int macio_probe(void)
 83{
 84	struct device_node *np;
 85
 86	np = of_find_compatible_node(NULL, "adb", "chrp,adb0");
 87	if (np) {
 88		of_node_put(np);
 89		return 0;
 90	}
 91	return -ENODEV;
 92}
 93
 94int macio_init(void)
 95{
 96	struct device_node *adbs;
 97	struct resource r;
 98	unsigned int irq;
 99
100	adbs = of_find_compatible_node(NULL, "adb", "chrp,adb0");
101	if (adbs == 0)
102		return -ENXIO;
103
104	if (of_address_to_resource(adbs, 0, &r)) {
105		of_node_put(adbs);
106		return -ENXIO;
107	}
108	adb = ioremap(r.start, sizeof(struct adb_regs));
109
110	out_8(&adb->ctrl.r, 0);
111	out_8(&adb->intr.r, 0);
112	out_8(&adb->error.r, 0);
113	out_8(&adb->active_hi.r, 0xff); /* for now, set all devices active */
114	out_8(&adb->active_lo.r, 0xff);
115	out_8(&adb->autopoll.r, APE);
116
117	irq = irq_of_parse_and_map(adbs, 0);
118	of_node_put(adbs);
119	if (request_irq(irq, macio_adb_interrupt, 0, "ADB", (void *)0)) {
120		printk(KERN_ERR "ADB: can't get irq %d\n", irq);
121		return -EAGAIN;
122	}
123	out_8(&adb->intr_enb.r, DFB | TAG);
124
125	printk("adb: mac-io driver 1.0 for unified ADB\n");
126
127	return 0;
128}
129
130static int macio_adb_autopoll(int devs)
131{
132	unsigned long flags;
133	
134	spin_lock_irqsave(&macio_lock, flags);
135	out_8(&adb->active_hi.r, devs >> 8);
136	out_8(&adb->active_lo.r, devs);
137	out_8(&adb->autopoll.r, devs? APE: 0);
138	spin_unlock_irqrestore(&macio_lock, flags);
139	return 0;
140}
141
142static int macio_adb_reset_bus(void)
143{
144	unsigned long flags;
145	int timeout = 1000000;
146
147	/* Hrm... we may want to not lock interrupts for so
148	 * long ... oh well, who uses that chip anyway ? :)
149	 * That function will be seldom used during boot
150	 * on rare machines, so...
151	 */
152	spin_lock_irqsave(&macio_lock, flags);
153	out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | ADB_RST);
154	while ((in_8(&adb->ctrl.r) & ADB_RST) != 0) {
155		if (--timeout == 0) {
156			out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) & ~ADB_RST);
157			spin_unlock_irqrestore(&macio_lock, flags);
158			return -1;
159		}
160	}
161	spin_unlock_irqrestore(&macio_lock, flags);
162	return 0;
163}
164
165/* Send an ADB command */
166static int macio_send_request(struct adb_request *req, int sync)
167{
168	unsigned long flags;
169	int i;
170	
171	if (req->data[0] != ADB_PACKET)
172		return -EINVAL;
173	
174	for (i = 0; i < req->nbytes - 1; ++i)
175		req->data[i] = req->data[i+1];
176	--req->nbytes;
177	
178	req->next = NULL;
179	req->sent = 0;
180	req->complete = 0;
181	req->reply_len = 0;
182
183	spin_lock_irqsave(&macio_lock, flags);
184	if (current_req != 0) {
185		last_req->next = req;
186		last_req = req;
187	} else {
188		current_req = last_req = req;
189		out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
190	}
191	spin_unlock_irqrestore(&macio_lock, flags);
192	
193	if (sync) {
194		while (!req->complete)
195			macio_adb_poll();
196	}
197
198	return 0;
199}
200
201static irqreturn_t macio_adb_interrupt(int irq, void *arg)
202{
203	int i, n, err;
204	struct adb_request *req = NULL;
205	unsigned char ibuf[16];
206	int ibuf_len = 0;
207	int complete = 0;
208	int autopoll = 0;
209	int handled = 0;
210
211	spin_lock(&macio_lock);
212	if (in_8(&adb->intr.r) & TAG) {
213		handled = 1;
214		if ((req = current_req) != 0) {
215			/* put the current request in */
216			for (i = 0; i < req->nbytes; ++i)
217				out_8(&adb->data[i].r, req->data[i]);
218			out_8(&adb->dcount.r, req->nbytes & HMB);
219			req->sent = 1;
220			if (req->reply_expected) {
221				out_8(&adb->ctrl.r, DTB + CRE);
222			} else {
223				out_8(&adb->ctrl.r, DTB);
224				current_req = req->next;
225				complete = 1;
226				if (current_req)
227					out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
228			}
229		}
230		out_8(&adb->intr.r, 0);
231	}
232
233	if (in_8(&adb->intr.r) & DFB) {
234		handled = 1;
235		err = in_8(&adb->error.r);
236		if (current_req && current_req->sent) {
237			/* this is the response to a command */
238			req = current_req;
239			if (err == 0) {
240				req->reply_len = in_8(&adb->dcount.r) & HMB;
241				for (i = 0; i < req->reply_len; ++i)
242					req->reply[i] = in_8(&adb->data[i].r);
243			}
244			current_req = req->next;
245			complete = 1;
246			if (current_req)
247				out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
248		} else if (err == 0) {
249			/* autopoll data */
250			n = in_8(&adb->dcount.r) & HMB;
251			for (i = 0; i < n; ++i)
252				ibuf[i] = in_8(&adb->data[i].r);
253			ibuf_len = n;
254			autopoll = (in_8(&adb->dcount.r) & APD) != 0;
255		}
256		out_8(&adb->error.r, 0);
257		out_8(&adb->intr.r, 0);
258	}
259	spin_unlock(&macio_lock);
260	if (complete && req) {
261	    void (*done)(struct adb_request *) = req->done;
262	    mb();
263	    req->complete = 1;
264	    /* Here, we assume that if the request has a done member, the
265    	     * struct request will survive to setting req->complete to 1
266	     */
267	    if (done)
268		(*done)(req);
269	}
270	if (ibuf_len)
271		adb_input(ibuf, ibuf_len, autopoll);
272
273	return IRQ_RETVAL(handled);
274}
275
276static void macio_adb_poll(void)
277{
278	unsigned long flags;
279
280	local_irq_save(flags);
281	if (in_8(&adb->intr.r) != 0)
282		macio_adb_interrupt(0, NULL);
283	local_irq_restore(flags);
284}