| /* | 
 |  * Driver for the ADB controller in the Mac I/O (Hydra) chip. | 
 |  */ | 
 | #include <stdarg.h> | 
 | #include <linux/types.h> | 
 | #include <linux/errno.h> | 
 | #include <linux/kernel.h> | 
 | #include <linux/delay.h> | 
 | #include <linux/spinlock.h> | 
 | #include <linux/interrupt.h> | 
 | #include <asm/prom.h> | 
 | #include <linux/adb.h> | 
 | #include <asm/io.h> | 
 | #include <asm/pgtable.h> | 
 | #include <asm/hydra.h> | 
 | #include <asm/irq.h> | 
 | #include <asm/system.h> | 
 | #include <linux/init.h> | 
 | #include <linux/ioport.h> | 
 |  | 
 | struct preg { | 
 | 	unsigned char r; | 
 | 	char pad[15]; | 
 | }; | 
 |  | 
 | struct adb_regs { | 
 | 	struct preg intr; | 
 | 	struct preg data[9]; | 
 | 	struct preg intr_enb; | 
 | 	struct preg dcount; | 
 | 	struct preg error; | 
 | 	struct preg ctrl; | 
 | 	struct preg autopoll; | 
 | 	struct preg active_hi; | 
 | 	struct preg active_lo; | 
 | 	struct preg test; | 
 | }; | 
 |  | 
 | /* Bits in intr and intr_enb registers */ | 
 | #define DFB	1		/* data from bus */ | 
 | #define TAG	2		/* transfer access grant */ | 
 |  | 
 | /* Bits in dcount register */ | 
 | #define HMB	0x0f		/* how many bytes */ | 
 | #define APD	0x10		/* auto-poll data */ | 
 |  | 
 | /* Bits in error register */ | 
 | #define NRE	1		/* no response error */ | 
 | #define DLE	2		/* data lost error */ | 
 |  | 
 | /* Bits in ctrl register */ | 
 | #define TAR	1		/* transfer access request */ | 
 | #define DTB	2		/* data to bus */ | 
 | #define CRE	4		/* command response expected */ | 
 | #define ADB_RST	8		/* ADB reset */ | 
 |  | 
 | /* Bits in autopoll register */ | 
 | #define APE	1		/* autopoll enable */ | 
 |  | 
 | static volatile struct adb_regs __iomem *adb; | 
 | static struct adb_request *current_req, *last_req; | 
 | static DEFINE_SPINLOCK(macio_lock); | 
 |  | 
 | static int macio_probe(void); | 
 | static int macio_init(void); | 
 | static irqreturn_t macio_adb_interrupt(int irq, void *arg); | 
 | static int macio_send_request(struct adb_request *req, int sync); | 
 | static int macio_adb_autopoll(int devs); | 
 | static void macio_adb_poll(void); | 
 | static int macio_adb_reset_bus(void); | 
 |  | 
 | struct adb_driver macio_adb_driver = { | 
 | 	"MACIO", | 
 | 	macio_probe, | 
 | 	macio_init, | 
 | 	macio_send_request, | 
 | 	/*macio_write,*/ | 
 | 	macio_adb_autopoll, | 
 | 	macio_adb_poll, | 
 | 	macio_adb_reset_bus | 
 | }; | 
 |  | 
 | int macio_probe(void) | 
 | { | 
 | 	struct device_node *np; | 
 |  | 
 | 	np = of_find_compatible_node(NULL, "adb", "chrp,adb0"); | 
 | 	if (np) { | 
 | 		of_node_put(np); | 
 | 		return 0; | 
 | 	} | 
 | 	return -ENODEV; | 
 | } | 
 |  | 
 | int macio_init(void) | 
 | { | 
 | 	struct device_node *adbs; | 
 | 	struct resource r; | 
 | 	unsigned int irq; | 
 |  | 
 | 	adbs = of_find_compatible_node(NULL, "adb", "chrp,adb0"); | 
 | 	if (adbs == 0) | 
 | 		return -ENXIO; | 
 |  | 
 | 	if (of_address_to_resource(adbs, 0, &r)) { | 
 | 		of_node_put(adbs); | 
 | 		return -ENXIO; | 
 | 	} | 
 | 	adb = ioremap(r.start, sizeof(struct adb_regs)); | 
 |  | 
 | 	out_8(&adb->ctrl.r, 0); | 
 | 	out_8(&adb->intr.r, 0); | 
 | 	out_8(&adb->error.r, 0); | 
 | 	out_8(&adb->active_hi.r, 0xff); /* for now, set all devices active */ | 
 | 	out_8(&adb->active_lo.r, 0xff); | 
 | 	out_8(&adb->autopoll.r, APE); | 
 |  | 
 | 	irq = irq_of_parse_and_map(adbs, 0); | 
 | 	of_node_put(adbs); | 
 | 	if (request_irq(irq, macio_adb_interrupt, 0, "ADB", (void *)0)) { | 
 | 		printk(KERN_ERR "ADB: can't get irq %d\n", irq); | 
 | 		return -EAGAIN; | 
 | 	} | 
 | 	out_8(&adb->intr_enb.r, DFB | TAG); | 
 |  | 
 | 	printk("adb: mac-io driver 1.0 for unified ADB\n"); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int macio_adb_autopoll(int devs) | 
 | { | 
 | 	unsigned long flags; | 
 | 	 | 
 | 	spin_lock_irqsave(&macio_lock, flags); | 
 | 	out_8(&adb->active_hi.r, devs >> 8); | 
 | 	out_8(&adb->active_lo.r, devs); | 
 | 	out_8(&adb->autopoll.r, devs? APE: 0); | 
 | 	spin_unlock_irqrestore(&macio_lock, flags); | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int macio_adb_reset_bus(void) | 
 | { | 
 | 	unsigned long flags; | 
 | 	int timeout = 1000000; | 
 |  | 
 | 	/* Hrm... we may want to not lock interrupts for so | 
 | 	 * long ... oh well, who uses that chip anyway ? :) | 
 | 	 * That function will be seldomly used during boot | 
 | 	 * on rare machines, so... | 
 | 	 */ | 
 | 	spin_lock_irqsave(&macio_lock, flags); | 
 | 	out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | ADB_RST); | 
 | 	while ((in_8(&adb->ctrl.r) & ADB_RST) != 0) { | 
 | 		if (--timeout == 0) { | 
 | 			out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) & ~ADB_RST); | 
 | 			return -1; | 
 | 		} | 
 | 	} | 
 | 	spin_unlock_irqrestore(&macio_lock, flags); | 
 | 	return 0; | 
 | } | 
 |  | 
 | /* Send an ADB command */ | 
 | static int macio_send_request(struct adb_request *req, int sync) | 
 | { | 
 | 	unsigned long flags; | 
 | 	int i; | 
 | 	 | 
 | 	if (req->data[0] != ADB_PACKET) | 
 | 		return -EINVAL; | 
 | 	 | 
 | 	for (i = 0; i < req->nbytes - 1; ++i) | 
 | 		req->data[i] = req->data[i+1]; | 
 | 	--req->nbytes; | 
 | 	 | 
 | 	req->next = NULL; | 
 | 	req->sent = 0; | 
 | 	req->complete = 0; | 
 | 	req->reply_len = 0; | 
 |  | 
 | 	spin_lock_irqsave(&macio_lock, flags); | 
 | 	if (current_req != 0) { | 
 | 		last_req->next = req; | 
 | 		last_req = req; | 
 | 	} else { | 
 | 		current_req = last_req = req; | 
 | 		out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR); | 
 | 	} | 
 | 	spin_unlock_irqrestore(&macio_lock, flags); | 
 | 	 | 
 | 	if (sync) { | 
 | 		while (!req->complete) | 
 | 			macio_adb_poll(); | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static irqreturn_t macio_adb_interrupt(int irq, void *arg) | 
 | { | 
 | 	int i, n, err; | 
 | 	struct adb_request *req = NULL; | 
 | 	unsigned char ibuf[16]; | 
 | 	int ibuf_len = 0; | 
 | 	int complete = 0; | 
 | 	int autopoll = 0; | 
 | 	int handled = 0; | 
 |  | 
 | 	spin_lock(&macio_lock); | 
 | 	if (in_8(&adb->intr.r) & TAG) { | 
 | 		handled = 1; | 
 | 		if ((req = current_req) != 0) { | 
 | 			/* put the current request in */ | 
 | 			for (i = 0; i < req->nbytes; ++i) | 
 | 				out_8(&adb->data[i].r, req->data[i]); | 
 | 			out_8(&adb->dcount.r, req->nbytes & HMB); | 
 | 			req->sent = 1; | 
 | 			if (req->reply_expected) { | 
 | 				out_8(&adb->ctrl.r, DTB + CRE); | 
 | 			} else { | 
 | 				out_8(&adb->ctrl.r, DTB); | 
 | 				current_req = req->next; | 
 | 				complete = 1; | 
 | 				if (current_req) | 
 | 					out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR); | 
 | 			} | 
 | 		} | 
 | 		out_8(&adb->intr.r, 0); | 
 | 	} | 
 |  | 
 | 	if (in_8(&adb->intr.r) & DFB) { | 
 | 		handled = 1; | 
 | 		err = in_8(&adb->error.r); | 
 | 		if (current_req && current_req->sent) { | 
 | 			/* this is the response to a command */ | 
 | 			req = current_req; | 
 | 			if (err == 0) { | 
 | 				req->reply_len = in_8(&adb->dcount.r) & HMB; | 
 | 				for (i = 0; i < req->reply_len; ++i) | 
 | 					req->reply[i] = in_8(&adb->data[i].r); | 
 | 			} | 
 | 			current_req = req->next; | 
 | 			complete = 1; | 
 | 			if (current_req) | 
 | 				out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR); | 
 | 		} else if (err == 0) { | 
 | 			/* autopoll data */ | 
 | 			n = in_8(&adb->dcount.r) & HMB; | 
 | 			for (i = 0; i < n; ++i) | 
 | 				ibuf[i] = in_8(&adb->data[i].r); | 
 | 			ibuf_len = n; | 
 | 			autopoll = (in_8(&adb->dcount.r) & APD) != 0; | 
 | 		} | 
 | 		out_8(&adb->error.r, 0); | 
 | 		out_8(&adb->intr.r, 0); | 
 | 	} | 
 | 	spin_unlock(&macio_lock); | 
 | 	if (complete && req) { | 
 | 	    void (*done)(struct adb_request *) = req->done; | 
 | 	    mb(); | 
 | 	    req->complete = 1; | 
 | 	    /* Here, we assume that if the request has a done member, the | 
 |     	     * struct request will survive to setting req->complete to 1 | 
 | 	     */ | 
 | 	    if (done) | 
 | 		(*done)(req); | 
 | 	} | 
 | 	if (ibuf_len) | 
 | 		adb_input(ibuf, ibuf_len, autopoll); | 
 |  | 
 | 	return IRQ_RETVAL(handled); | 
 | } | 
 |  | 
 | static void macio_adb_poll(void) | 
 | { | 
 | 	unsigned long flags; | 
 |  | 
 | 	local_irq_save(flags); | 
 | 	if (in_8(&adb->intr.r) != 0) | 
 | 		macio_adb_interrupt(0, NULL); | 
 | 	local_irq_restore(flags); | 
 | } |