diff options
Diffstat (limited to 'drivers/usb/dwc3/gadget.c')
| -rw-r--r-- | drivers/usb/dwc3/gadget.c | 121 |
1 files changed, 81 insertions, 40 deletions
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 011ac3ccfbe7..e4e872c703f1 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1,4 +1,4 @@ -/** +/* * gadget.c - DesignWare USB3 DRD Controller Gadget Framework Link * * Copyright (C) 2010-2011 Texas Instruments Incorporated - http://www.ti.com @@ -36,13 +36,12 @@ #include "io.h" /** - * dwc3_gadget_set_test_mode - Enables USB2 Test Modes + * dwc3_gadget_set_test_mode - enables usb2 test modes * @dwc: pointer to our context structure * @mode: the mode to set (J, K SE0 NAK, Force Enable) * - * Caller should take care of locking. This function will - * return 0 on success or -EINVAL if wrong Test Selector - * is passed + * Caller should take care of locking. This function will return 0 on + * success or -EINVAL if wrong Test Selector is passed. */ int dwc3_gadget_set_test_mode(struct dwc3 *dwc, int mode) { @@ -69,7 +68,7 @@ int dwc3_gadget_set_test_mode(struct dwc3 *dwc, int mode) } /** - * dwc3_gadget_get_link_state - Gets current state of USB Link + * dwc3_gadget_get_link_state - gets current state of usb link * @dwc: pointer to our context structure * * Caller should take care of locking. This function will @@ -85,7 +84,7 @@ int dwc3_gadget_get_link_state(struct dwc3 *dwc) } /** - * dwc3_gadget_set_link_state - Sets USB Link to a particular State + * dwc3_gadget_set_link_state - sets usb link to a particular state * @dwc: pointer to our context structure * @state: the state to put link into * @@ -143,8 +142,8 @@ int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state) } /** - * dwc3_ep_inc_trb() - Increment a TRB index. - * @index - Pointer to the TRB index to increment. + * dwc3_ep_inc_trb - increment a trb index. + * @index: Pointer to the TRB index to increment. * * The index should never point to the link TRB. After incrementing, * if it is point to the link TRB, wrap around to the beginning. The @@ -157,16 +156,34 @@ static void dwc3_ep_inc_trb(u8 *index) *index = 0; } +/** + * dwc3_ep_inc_enq - increment endpoint's enqueue pointer + * @dep: The endpoint whose enqueue pointer we're incrementing + */ static void dwc3_ep_inc_enq(struct dwc3_ep *dep) { dwc3_ep_inc_trb(&dep->trb_enqueue); } +/** + * dwc3_ep_inc_deq - increment endpoint's dequeue pointer + * @dep: The endpoint whose enqueue pointer we're incrementing + */ static void dwc3_ep_inc_deq(struct dwc3_ep *dep) { dwc3_ep_inc_trb(&dep->trb_dequeue); } +/** + * dwc3_gadget_giveback - call struct usb_request's ->complete callback + * @dep: The endpoint to whom the request belongs to + * @req: The request we're giving back + * @status: completion code for the request + * + * Must be called with controller's lock held and interrupts disabled. This + * function will unmap @req and call its ->complete() callback to notify upper + * layers that it has completed. + */ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req, int status) { @@ -193,6 +210,15 @@ void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req, pm_runtime_put(dwc->dev); } +/** + * dwc3_send_gadget_generic_command - issue a generic command for the controller + * @dwc: pointer to the controller context + * @cmd: the command to be issued + * @param: command parameter + * + * Caller should take care of locking. Issue @cmd with a given @param to @dwc + * and wait for its completion. + */ int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned cmd, u32 param) { u32 timeout = 500; @@ -225,6 +251,15 @@ int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned cmd, u32 param) static int __dwc3_gadget_wakeup(struct dwc3 *dwc); +/** + * dwc3_send_gadget_ep_cmd - issue an endpoint command + * @dep: the endpoint to which the command is going to be issued + * @cmd: the command to be issued + * @params: parameters to the command + * + * Caller should handle locking. This function will issue @cmd with given + * @params to @dep and wait for its completion. + */ int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned cmd, struct dwc3_gadget_ep_cmd_params *params) { @@ -422,36 +457,38 @@ static void dwc3_free_trb_pool(struct dwc3_ep *dep) static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep); /** - * dwc3_gadget_start_config - Configure EP resources + * dwc3_gadget_start_config - configure ep resources * @dwc: pointer to our controller context structure * @dep: endpoint that is being enabled * - * The assignment of transfer resources cannot perfectly follow the - * data book due to the fact that the controller driver does not have - * all knowledge of the configuration in advance. It is given this - * information piecemeal by the composite gadget framework after every - * SET_CONFIGURATION and SET_INTERFACE. Trying to follow the databook - * programming model in this scenario can cause errors. For two - * reasons: + * Issue a %DWC3_DEPCMD_DEPSTARTCFG command to @dep. After the command's + * completion, it will set Transfer Resource for all available endpoints. * - * 1) The databook says to do DEPSTARTCFG for every SET_CONFIGURATION - * and SET_INTERFACE (8.1.5). This is incorrect in the scenario of - * multiple interfaces. + * The assignment of transfer resources cannot perfectly follow the data book + * due to the fact that the controller driver does not have all knowledge of the + * configuration in advance. It is given this information piecemeal by the + * composite gadget framework after every SET_CONFIGURATION and + * SET_INTERFACE. Trying to follow the databook programming model in this + * scenario can cause errors. For two reasons: * - * 2) The databook does not mention doing more DEPXFERCFG for new + * 1) The databook says to do %DWC3_DEPCMD_DEPSTARTCFG for every + * %USB_REQ_SET_CONFIGURATION and %USB_REQ_SET_INTERFACE (8.1.5). This is + * incorrect in the scenario of multiple interfaces. + * + * 2) The databook does not mention doing more %DWC3_DEPCMD_DEPXFERCFG for new * endpoint on alt setting (8.1.6). * * The following simplified method is used instead: * - * All hardware endpoints can be assigned a transfer resource and this - * setting will stay persistent until either a core reset or - * hibernation. So whenever we do a DEPSTARTCFG(0) we can go ahead and - * do DEPXFERCFG for every hardware endpoint as well. We are + * All hardware endpoints can be assigned a transfer resource and this setting + * will stay persistent until either a core reset or hibernation. So whenever we + * do a %DWC3_DEPCMD_DEPSTARTCFG(0) we can go ahead and do + * %DWC3_DEPCMD_DEPXFERCFG for every hardware endpoint as well. We are * guaranteed that there are as many transfer resources as endpoints. * - * This function is called for each endpoint when it is being enabled - * but is triggered only when called for EP0-out, which always happens - * first, and which should only happen in one of the above conditions. + * This function is called for each endpoint when it is being enabled but is + * triggered only when called for EP0-out, which always happens first, and which + * should only happen in one of the above conditions. */ static int dwc3_gadget_start_config(struct dwc3 *dwc, struct dwc3_ep *dep) { @@ -569,11 +606,13 @@ static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep) } /** - * __dwc3_gadget_ep_enable - Initializes a HW endpoint + * __dwc3_gadget_ep_enable - initializes a hw endpoint * @dep: endpoint to be initialized - * @desc: USB Endpoint Descriptor + * @modify: if true, modify existing endpoint configuration + * @restore: if true, restore endpoint configuration from scratch buffer * - * Caller should take care of locking + * Caller should take care of locking. Execute all necessary commands to + * initialize a HW endpoint so it can be used by a gadget driver. */ static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep, bool modify, bool restore) @@ -685,11 +724,13 @@ static void dwc3_remove_requests(struct dwc3 *dwc, struct dwc3_ep *dep) } /** - * __dwc3_gadget_ep_disable - Disables a HW endpoint + * __dwc3_gadget_ep_disable - disables a hw endpoint * @dep: the endpoint to disable * - * This function also removes requests which are currently processed ny the - * hardware and those which are not yet scheduled. + * This function undoes what __dwc3_gadget_ep_enable did and also removes + * requests which are currently being processed by the hardware and those which + * are not yet scheduled. + * * Caller should take care of locking. */ static int __dwc3_gadget_ep_disable(struct dwc3_ep *dep) @@ -932,7 +973,7 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep, } /** - * dwc3_ep_prev_trb() - Returns the previous TRB in the ring + * dwc3_ep_prev_trb - returns the previous TRB in the ring * @dep: The endpoint with the TRB ring * @index: The index of the current TRB in the ring * @@ -1729,8 +1770,8 @@ static irqreturn_t dwc3_interrupt(int irq, void *_dwc); static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc); /** - * dwc3_gadget_setup_nump - Calculate and initialize NUMP field of DCFG - * dwc: pointer to our context structure + * dwc3_gadget_setup_nump - calculate and initialize NUMP field of %DWC3_DCFG + * @dwc: pointer to our context structure * * The following looks like complex but it's actually very simple. In order to * calculate the number of packets we can burst at once on OUT transfers, we're @@ -1789,7 +1830,7 @@ static int __dwc3_gadget_start(struct dwc3 *dwc) reg = dwc3_readl(dwc->regs, DWC3_DCFG); reg &= ~(DWC3_DCFG_SPEED_MASK); - /** + /* * WORKAROUND: DWC3 revision < 2.20a have an issue * which would cause metastability state on Run/Stop * bit if we try to force the IP to USB2-only mode. @@ -2859,7 +2900,7 @@ static void dwc3_gadget_hibernation_interrupt(struct dwc3 *dwc, { unsigned int is_ss = evtinfo & BIT(4); - /** + /* * WORKAROUND: DWC3 revison 2.20a with hibernation support * have a known issue which can cause USB CV TD.9.23 to fail * randomly. @@ -3089,7 +3130,7 @@ out: } /** - * dwc3_gadget_init - Initializes gadget related registers + * dwc3_gadget_init - initializes gadget related registers * @dwc: pointer to our controller context structure * * Returns 0 on success otherwise negative errno. |