stmmac: review driver when run kernel-doc

When run ./scripts/kernel-doc several warnings are reported
so this patch fix them.
Also it reviews many comments and adds new ones.
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/stmicro/stmmac/dwmac-sti.c

-/**
+/*
  * dwmac-sti.c - STMicroelectronics DWMAC Specific Glue layer
  *
  * Copyright (C) 2003-2014 STMicroelectronics (R&D) Limited
@@ -37,9 +37,8 @@
 #define IS_PHY_IF_MODE_GBIT(iface)	(IS_PHY_IF_MODE_RGMII(iface) || \
 					 iface == PHY_INTERFACE_MODE_GMII)
 
-/* STiH4xx register definitions (STiH415/STiH416/STiH407/STiH410 families) */
-
-/**
+/* STiH4xx register definitions (STiH415/STiH416/STiH407/STiH410 families)
+ *
  * Below table summarizes the clock requirement and clock sources for
  * supported phy interface modes with link speeds.
  * ________________________________________________
@@ -78,9 +77,7 @@
 #define STIH4XX_ETH_SEL_INTERNAL_NOTEXT_PHYCLK	BIT(7)
 #define STIH4XX_ETH_SEL_TXCLK_NOT_CLK125	BIT(6)
 
-/* STiD127 register definitions */
-
-/**
+/* STiD127 register definitions
  *-----------------------
  * src	 |BIT(6)| BIT(7)|
  *-----------------------
@@ -106,13 +103,13 @@
 #define EN_MASK		GENMASK(1, 1)
 #define EN		BIT(1)
 
-/**
+/*
  * 3 bits [4:2]
  *	000-GMII/MII
  *	001-RGMII
  *	010-SGMII
  *	100-RMII
-*/
+ */
 #define MII_PHY_SEL_MASK	GENMASK(4, 2)
 #define ETH_PHY_SEL_RMII	BIT(4)
 #define ETH_PHY_SEL_SGMII	BIT(3)

drivers/net/ethernet/stmicro/stmmac/dwmac-sunxi.c

-/**
+/*
  * dwmac-sunxi.c - Allwinner sunxi DWMAC specific glue layer
  *
  * Copyright (C) 2013 Chen-Yu Tsai

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

@@ -125,8 +125,8 @@ static void stmmac_exit_fs(void);
 
 /**
  * stmmac_verify_args - verify the driver parameters.
- * Description: it verifies if some wrong parameter is passed to the driver.
- * Note that wrong parameters are replaced with the default values.
+ * Description: it checks the driver parameters and set a default in case of
+ * errors.
  */
 static void stmmac_verify_args(void)
 {
@@ -204,7 +204,7 @@ static inline u32 stmmac_tx_avail(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_hw_fix_mac_speed: callback for speed selection
+ * stmmac_hw_fix_mac_speed - callback for speed selection
  * @priv: driver private structure
  * Description: on some platforms (e.g. ST), some HW system configuraton
  * registers have to be set according to the link speed negotiated.
@@ -218,9 +218,10 @@ static inline void stmmac_hw_fix_mac_speed(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_enable_eee_mode: Check and enter in LPI mode
+ * stmmac_enable_eee_mode - check and enter in LPI mode
  * @priv: driver private structure
- * Description: this function is to verify and enter in LPI mode for EEE.
+ * Description: this function is to verify and enter in LPI mode in case of
+ * EEE.
  */
 static void stmmac_enable_eee_mode(struct stmmac_priv *priv)
 {
@@ -231,7 +232,7 @@ static void stmmac_enable_eee_mode(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_disable_eee_mode: disable/exit from EEE
+ * stmmac_disable_eee_mode - disable and exit from LPI mode
  * @priv: driver private structure
  * Description: this function is to exit and disable EEE in case of
  * LPI state is true. This is called by the xmit.
@@ -244,7 +245,7 @@ void stmmac_disable_eee_mode(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_eee_ctrl_timer: EEE TX SW timer.
+ * stmmac_eee_ctrl_timer - EEE TX SW timer.
  * @arg : data hook
  * Description:
  *  if there is no data transfer and if we are not in LPI state,
@@ -259,13 +260,12 @@ static void stmmac_eee_ctrl_timer(unsigned long arg)
 }
 
 /**
- * stmmac_eee_init: init EEE
+ * stmmac_eee_init - init EEE
  * @priv: driver private structure
  * Description:
- *  If the EEE support has been enabled while configuring the driver,
- *  if the GMAC actually supports the EEE (from the HW cap reg) and the
- *  phy can also manage EEE, so enable the LPI state and start the timer
- *  to verify if the tx path can enter in LPI state.
+ *  if the GMAC supports the EEE (from the HW cap reg) and the phy device
+ *  can also manage EEE, this function enable the LPI state and start related
+ *  timer.
  */
 bool stmmac_eee_init(struct stmmac_priv *priv)
 {
@@ -332,7 +332,7 @@ bool stmmac_eee_init(struct stmmac_priv *priv)
 	return ret;
 }
 
-/* stmmac_get_tx_hwtstamp: get HW TX timestamps
+/* stmmac_get_tx_hwtstamp - get HW TX timestamps
  * @priv: driver private structure
  * @entry : descriptor index to be used.
  * @skb : the socket buffer
@@ -374,7 +374,7 @@ static void stmmac_get_tx_hwtstamp(struct stmmac_priv *priv,
 	return;
 }
 
-/* stmmac_get_rx_hwtstamp: get HW RX timestamps
+/* stmmac_get_rx_hwtstamp - get HW RX timestamps
  * @priv: driver private structure
  * @entry : descriptor index to be used.
  * @skb : the socket buffer
@@ -630,11 +630,11 @@ static int stmmac_hwtstamp_ioctl(struct net_device *dev, struct ifreq *ifr)
 }
 
 /**
- * stmmac_init_ptp: init PTP
+ * stmmac_init_ptp - init PTP
  * @priv: driver private structure
- * Description: this is to verify if the HW supports the PTPv1 or v2.
+ * Description: this is to verify if the HW supports the PTPv1 or PTPv2.
  * This is done by looking at the HW cap. register.
- * Also it registers the ptp driver.
+ * This function also registers the ptp driver.
  */
 static int stmmac_init_ptp(struct stmmac_priv *priv)
 {
@@ -676,9 +676,13 @@ static void stmmac_release_ptp(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_adjust_link
+ * stmmac_adjust_link - adjusts the link parameters
  * @dev: net device structure
- * Description: it adjusts the link parameters.
+ * Description: this is the helper called by the physical abstraction layer
+ * drivers to communicate the phy link status. According the speed and duplex
+ * this driver can invoke registered glue-logic as well.
+ * It also invoke the eee initialization because it could happen when switch
+ * on different networks (that are eee capable).
  */
 static void stmmac_adjust_link(struct net_device *dev)
 {
@@ -768,7 +772,7 @@ static void stmmac_adjust_link(struct net_device *dev)
 }
 
 /**
- * stmmac_check_pcs_mode: verify if RGMII/SGMII is supported
+ * stmmac_check_pcs_mode - verify if RGMII/SGMII is supported
  * @priv: driver private structure
  * Description: this is to verify if the HW supports the PCS.
  * Physical Coding Sublayer (PCS) interface that can be used when the MAC is
@@ -857,7 +861,7 @@ static int stmmac_init_phy(struct net_device *dev)
 }
 
 /**
- * stmmac_display_ring: display ring
+ * stmmac_display_ring - display ring
  * @head: pointer to the head of the ring passed.
  * @size: size of the ring.
  * @extend_desc: to verify if extended descriptors are used.
@@ -925,7 +929,7 @@ static int stmmac_set_bfsize(int mtu, int bufsize)
 }
 
 /**
- * stmmac_clear_descriptors: clear descriptors
+ * stmmac_clear_descriptors - clear descriptors
  * @priv: driver private structure
  * Description: this function is called to clear the tx and rx descriptors
  * in case of both basic and extended descriptors are used.
@@ -957,6 +961,15 @@ static void stmmac_clear_descriptors(struct stmmac_priv *priv)
 						     (i == txsize - 1));
 }
 
+/**
+ * stmmac_init_rx_buffers - init the RX descriptor buffer.
+ * @priv: driver private structure
+ * @p: descriptor pointer
+ * @i: descriptor index
+ * @flags: gfp flag.
+ * Description: this function is called to allocate a receive buffer, perform
+ * the DMA mapping and init the descriptor.
+ */
 static int stmmac_init_rx_buffers(struct stmmac_priv *priv, struct dma_desc *p,
 				  int i, gfp_t flags)
 {
@@ -1001,7 +1014,8 @@ static void stmmac_free_rx_buffers(struct stmmac_priv *priv, int i)
 /**
  * init_dma_desc_rings - init the RX/TX descriptor rings
  * @dev: net device structure
- * Description:  this function initializes the DMA RX/TX descriptors
+ * @flags: gfp flag.
+ * Description: this function initializes the DMA RX/TX descriptors
  * and allocates the socket buffers. It suppors the chained and ring
  * modes.
  */
@@ -1138,6 +1152,14 @@ static void dma_free_tx_skbufs(struct stmmac_priv *priv)
 	}
 }
 
+/**
+ * alloc_dma_desc_resources - alloc TX/RX resources.
+ * @priv: private structure
+ * Description: according to which descriptor can be used (extend or basic)
+ * this function allocates the resources for TX and RX paths. In case of
+ * reception, for example, it pre-allocated the RX socket buffer in order to
+ * allow zero-copy mechanism.
+ */
 static int alloc_dma_desc_resources(struct stmmac_priv *priv)
 {
 	unsigned int txsize = priv->dma_tx_size;
@@ -1249,8 +1271,8 @@ static void free_dma_desc_resources(struct stmmac_priv *priv)
 /**
  *  stmmac_dma_operation_mode - HW DMA operation mode
  *  @priv: driver private structure
- *  Description: it sets the DMA operation mode: tx/rx DMA thresholds
- *  or Store-And-Forward capability.
+ *  Description: it is used for configuring the DMA operation mode register in
+ *  order to program the tx/rx DMA thresholds or Store-And-Forward mode.
  */
 static void stmmac_dma_operation_mode(struct stmmac_priv *priv)
 {
@@ -1271,9 +1293,9 @@ static void stmmac_dma_operation_mode(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_tx_clean:
+ * stmmac_tx_clean - to manage the transmission completion
  * @priv: driver private structure
- * Description: it reclaims resources after transmission completes.
+ * Description: it reclaims the transmit resources after transmission completes.
  */
 static void stmmac_tx_clean(struct stmmac_priv *priv)
 {
@@ -1372,10 +1394,10 @@ static inline void stmmac_disable_dma_irq(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_tx_err: irq tx error mng function
+ * stmmac_tx_err - to manage the tx error
  * @priv: driver private structure
  * Description: it cleans the descriptors and restarts the transmission
- * in case of errors.
+ * in case of transmission errors.
  */
 static void stmmac_tx_err(struct stmmac_priv *priv)
 {
@@ -1403,12 +1425,11 @@ static void stmmac_tx_err(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_dma_interrupt: DMA ISR
+ * stmmac_dma_interrupt - DMA ISR
  * @priv: driver private structure
  * Description: this is the DMA ISR. It is called by the main ISR.
- * It calls the dwmac dma routine to understand which type of interrupt
- * happened. In case of there is a Normal interrupt and either TX or RX
- * interrupt happened so the NAPI is scheduled.
+ * It calls the dwmac dma routine and schedule poll method in case of some
+ * work can be done.
  */
 static void stmmac_dma_interrupt(struct stmmac_priv *priv)
 {
@@ -1451,6 +1472,12 @@ static void stmmac_mmc_setup(struct stmmac_priv *priv)
 		pr_info(" No MAC Management Counters available\n");
 }
 
+/**
+ * stmmac_get_synopsys_id - return the SYINID.
+ * @priv: driver private structure
+ * Description: this simple function is to decode and return the SYINID
+ * starting from the HW core register.
+ */
 static u32 stmmac_get_synopsys_id(struct stmmac_priv *priv)
 {
 	u32 hwid = priv->hw->synopsys_uid;
@@ -1469,11 +1496,11 @@ static u32 stmmac_get_synopsys_id(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_selec_desc_mode: to select among: normal/alternate/extend descriptors
+ * stmmac_selec_desc_mode - to select among: normal/alternate/extend descriptors
  * @priv: driver private structure
  * Description: select the Enhanced/Alternate or Normal descriptors.
- * In case of Enhanced/Alternate, it looks at the extended descriptors are
- * supported by the HW cap. register.
+ * In case of Enhanced/Alternate, it checks if the extended descriptors are
+ * supported by the HW capability register.
  */
 static void stmmac_selec_desc_mode(struct stmmac_priv *priv)
 {
@@ -1495,7 +1522,7 @@ static void stmmac_selec_desc_mode(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_get_hw_features: get MAC capabilities from the HW cap. register.
+ * stmmac_get_hw_features - get MAC capabilities from the HW cap. register.
  * @priv: driver private structure
  * Description:
  *  new GMAC chip generations have a new register to indicate the
@@ -1553,7 +1580,7 @@ static int stmmac_get_hw_features(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_check_ether_addr: check if the MAC addr is valid
+ * stmmac_check_ether_addr - check if the MAC addr is valid
  * @priv: driver private structure
  * Description:
  * it is to verify if the MAC address is valid, in case of failures it
@@ -1572,7 +1599,7 @@ static void stmmac_check_ether_addr(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_init_dma_engine: DMA init.
+ * stmmac_init_dma_engine - DMA init.
  * @priv: driver private structure
  * Description:
  * It inits the DMA invoking the specific MAC/GMAC callback.
@@ -1601,7 +1628,7 @@ static int stmmac_init_dma_engine(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_tx_timer: mitigation sw timer for tx.
+ * stmmac_tx_timer - mitigation sw timer for tx.
  * @data: data pointer
  * Description:
  * This is the timer handler to directly invoke the stmmac_tx_clean.
@@ -1614,7 +1641,7 @@ static void stmmac_tx_timer(unsigned long data)
 }
 
 /**
- * stmmac_init_tx_coalesce: init tx mitigation options.
+ * stmmac_init_tx_coalesce - init tx mitigation options.
  * @priv: driver private structure
  * Description:
  * This inits the transmit coalesce parameters: i.e. timer rate,
@@ -1633,10 +1660,13 @@ static void stmmac_init_tx_coalesce(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_hw_setup: setup mac in a usable state.
+ * stmmac_hw_setup - setup mac in a usable state.
  *  @dev : pointer to the device structure.
  *  Description:
- *  This function sets up the ip in a usable state.
+ *  this is the main function to setup the HW in a usable state because the
+ *  dma engine is reset, the core registers are configured (e.g. AXI,
+ *  Checksum features, timers). The DMA is ready to start receiving and
+ *  transmitting.
  *  Return value:
  *  0 on success and an appropriate (-)ve integer as defined in errno.h
  *  file on failure.
@@ -1874,7 +1904,7 @@ static int stmmac_release(struct net_device *dev)
 }
 
 /**
- *  stmmac_xmit: Tx entry point of the driver
+ *  stmmac_xmit - Tx entry point of the driver
  *  @skb : the socket buffer
  *  @dev : device pointer
  *  Description : this is the tx entry point of the driver.
@@ -2049,7 +2079,7 @@ static void stmmac_rx_vlan(struct net_device *dev, struct sk_buff *skb)
 
 
 /**
- * stmmac_rx_refill: refill used skb preallocated buffers
+ * stmmac_rx_refill - refill used skb preallocated buffers
  * @priv: driver private structure
  * Description : this is to reallocate the skb for the reception process
  * that is based on zero-copy.
@@ -2100,7 +2130,7 @@ static inline void stmmac_rx_refill(struct stmmac_priv *priv)
 }
 
 /**
- * stmmac_rx_refill: refill used skb preallocated buffers
+ * stmmac_rx - manage the receive process
  * @priv: driver private structure
  * @limit: napi bugget.
  * Description :  this the function called by the napi poll method.
@@ -2369,8 +2399,11 @@ static int stmmac_set_features(struct net_device *netdev,
  *  @irq: interrupt number.
  *  @dev_id: to pass the net device pointer.
  *  Description: this is the main driver interrupt service routine.
- *  It calls the DMA ISR and also the core ISR to manage PMT, MMC, LPI
- *  interrupts.
+ *  It can call:
+ *  o DMA service routine (to manage incoming frame reception and transmission
+ *    status)
+ *  o Core interrupts to manage: remote wake-up, management counter, LPI
+ *    interrupts.
  */
 static irqreturn_t stmmac_interrupt(int irq, void *dev_id)
 {
@@ -2657,11 +2690,10 @@ static const struct net_device_ops stmmac_netdev_ops = {
 /**
  *  stmmac_hw_init - Init the MAC device
  *  @priv: driver private structure
- *  Description: this function detects which MAC device
- *  (GMAC/MAC10-100) has to attached, checks the HW capability
- *  (if supported) and sets the driver's features (for example
- *  to use the ring or chaine mode or support the normal/enh
- *  descriptor structure).
+ *  Description: this function is to configure the MAC device according to
+ *  some platform parameters or the HW capability register. It prepares the
+ *  driver to use either ring or chain modes and to setup either enhanced or
+ *  normal descriptors.
  */
 static int stmmac_hw_init(struct stmmac_priv *priv)
 {
@@ -2917,6 +2949,13 @@ int stmmac_dvr_remove(struct net_device *ndev)
 }
 EXPORT_SYMBOL_GPL(stmmac_dvr_remove);
 
+/**
+ * stmmac_suspend - suspend callback
+ * @ndev: net device pointer
+ * Description: this is the function to suspend the device and it is called
+ * by the platform driver to stop the network queue, release the resources,
+ * program the PMT register (for WoL), clean and release driver resources.
+ */
 int stmmac_suspend(struct net_device *ndev)
 {
 	struct stmmac_priv *priv = netdev_priv(ndev);
@@ -2960,6 +2999,12 @@ int stmmac_suspend(struct net_device *ndev)
 }
 EXPORT_SYMBOL_GPL(stmmac_suspend);
 
+/**
+ * stmmac_resume - resume callback
+ * @ndev: net device pointer
+ * Description: when resume this function is invoked to setup the DMA and CORE
+ * in a usable state.
+ */
 int stmmac_resume(struct net_device *ndev)
 {
 	struct stmmac_priv *priv = netdev_priv(ndev);

drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c

@@ -51,7 +51,11 @@ MODULE_DEVICE_TABLE(of, stmmac_dt_ids);
 
 #ifdef CONFIG_OF
 
-/* This function validates the number of Multicast filtering bins specified
+/**
+ * dwmac1000_validate_mcast_bins - validates the number of Multicast filter bins
+ * @mcast_bins: Multicast filtering bins
+ * Description:
+ * this function validates the number of Multicast filtering bins specified
  * by the configuration through the device tree. The Synopsys GMAC supports
  * 64 bins, 128 bins, or 256 bins. "bins" refer to the division of CRC
  * number space. 64 bins correspond to 6 bits of the CRC, 128 corresponds
@@ -77,7 +81,11 @@ static int dwmac1000_validate_mcast_bins(int mcast_bins)
 	return x;
 }
 
-/* This function validates the number of Unicast address entries supported
+/**
+ * dwmac1000_validate_ucast_entries - validate the Unicast address entries
+ * @ucast_entries: number of Unicast address entries
+ * Description:
+ * This function validates the number of Unicast address entries supported
  * by a particular Synopsys 10/100/1000 controller. The Synopsys controller
  * supports 1, 32, 64, or 128 Unicast filter entries for it's Unicast filter
  * logic. This function validates a valid, supported configuration is
@@ -103,6 +111,15 @@ static int dwmac1000_validate_ucast_entries(int ucast_entries)
 	return x;
 }
 
+/**
+ * stmmac_probe_config_dt - parse device-tree driver parameters
+ * @pdev: platform_device structure
+ * @plat: driver data platform structure
+ * @mac: MAC address to use
+ * Description:
+ * this function is to read the driver parameters from device-tree and
+ * set some private fields that will be used by the main at runtime.
+ */
 static int stmmac_probe_config_dt(struct platform_device *pdev,
 				  struct plat_stmmacenet_data *plat,
 				  const char **mac)
@@ -242,11 +259,11 @@ static int stmmac_probe_config_dt(struct platform_device *pdev,
 #endif /* CONFIG_OF */
 
 /**
- * stmmac_pltfr_probe
+ * stmmac_pltfr_probe - platform driver probe.
  * @pdev: platform device pointer
- * Description: platform_device probe function. It allocates
- * the necessary resources and invokes the main to init
- * the net device, register the mdio bus etc.
+ * Description: platform_device probe function. It is to allocate
+ * the necessary platform resources, invoke custom helper (if required) and
+ * invoke the main probe function.
  */
 static int stmmac_pltfr_probe(struct platform_device *pdev)
 {
@@ -363,6 +380,13 @@ static int stmmac_pltfr_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_PM_SLEEP
+/**
+ * stmmac_pltfr_suspend
+ * @dev: device pointer
+ * Description: this function is invoked when suspend the driver and it direcly
+ * call the main suspend function and then, if required, on some platform, it
+ * can call an exit helper.
+ */
 static int stmmac_pltfr_suspend(struct device *dev)
 {
 	int ret;
@@ -377,6 +401,13 @@ static int stmmac_pltfr_suspend(struct device *dev)
 	return ret;
 }
 
+/**
+ * stmmac_pltfr_resume
+ * @dev: device pointer
+ * Description: this function is invoked when resume the driver before calling
+ * the main resume function, on some platforms, it can call own init helper
+ * if required.
+ */
 static int stmmac_pltfr_resume(struct device *dev)
 {
 	struct net_device *ndev = dev_get_drvdata(dev);